



CX3PYRIGHT DEPOSIT 



THE 



MANUFACTURE OF LEATHER: 



^ 



BEING A 

DESCRIPTION OF ALL OF THE PROCESSES FOR THE TANNING, 

TAWING, CURRYING, FINISHING, AND DYEING 

OF EVERY KIND OF LEATHER; 

INCLUDING THE 

VARIOUS RAW MATERIALS AND THE METHODS FOR DETERMINING THEIR 
VALUES ; THE TOOLS, MACHINES, AND ALL DETAILS OF IMPORTANCE 
CONNECTED WITH AN INTELLIGENT AND PROFITABLE PROS- 
ECUTION OF THE ART, WITH SPECIAL REFERENCE TO 
THE BEST AMERICAN PRACTICE. 

TO WHICH ARE ADDED 

COMPLETE LISTS OF ALL AMERICAN PATENTS FOR MATERIALS, PROCESSES, 
TOOLS, AND MACHINES FOR TANNING, CURRYING, ETC. 



(3 , BY 

/ 1 

-y^ CHARLES THOMAS DAVIS. 

ILLUSTRATED BY THREE HUNDRED AND TWO ENGRAVINGS, 

AND 

TWELVE SAMPLES OF DYED LEATHERS. 



DEC 10 18i4 



PHILADELPHIA: 
HENEY CAEEY BAIRD & C 07^ 

INDUSTRIAL PUBLISHERS, BOOKSELLERS AND IMPORTERS, 
No. 810 WALNUT STREET. 

A LOXDOI^ : 

SAMPSON LOW, MARSTON, SEARLE & RIVINGTON, 
CROWN BUILDINGS, 188 FLEET STREET. 

1885. 




&- 



^'^y 



5 



Copyright by 

CHAKLES THOMAS DAVIS, 
1884. 



COPl'RIGHT BY 

HENRY CAREY BAIRD & CO. 

1884. 




^.W^ 



COLLINS, PRINTER. 



PREFACE 



Considering the importance of the leather industry, it seems 
strange that up to the present time it should in technical 
literature have been so much neglected. 

There is not in England nor is there in America a single 
current book broadly treating all the branches of this subject, 
and the object of the present volume is fully to explain the 
details of manufacturing all kinds of leather in common use, 
and produced from hides and skins by the agency of the usual 
tanning substances. 

The author has not been satisfied to make use of the matter 
found in obsolete books, but has preferred to present a view of 
the state of the art as it to-day exists in the United States. 

The tools, machines, and in fact nearly all the mechanical 
appliances illustrated in the present treatise are of American 
origin, and in common use in the numerous tanneries and 
leather-finishing shops of the country. 

The collection, compilation, and collation of the vast amount 
of technical and detailed information attainable relating to the 
various processes, and to the construction of the numerous ma- 
chines herein described, have required almost herculean labor. 
But the work has been greatly aided by many of the leading 
tanners and curriers of the United States, who have not only 
placed at the author's disposal every opportunity for personal 
observation, but have promptly and courteously responded to 



IV PREFACE. 

his letters when containing requests for information. It is 
doubtful if such facilities as have been extended to him 
would be granted to a like professional writer on technical 
subjects in any other country in tlje world. 

The enormous development of American leather manufactur- 
ing industries is a source of much congratulation. There are of 
course in this manufacture, as in all others, times of depression, 
but the natural facilities for obtaining the raw material, the 
great ingenuity of our people, and the steady increase in the 
export demand, added to the large home consumption of leather, 
are certain to keep the United States in the position of the 
leading leather-producing country of the world. 

The invention and employment of a large number of mechan- 
ical appliances have done much to stimulate and cheapen leather 
production in the times just passed, and those manufacturers 
who have clung to the old-fasliioned metliods of tanning and 
finishing leather by hand have found their business absorbed 
by more enterprising firms. 

Sucli results were only natural, and it is therefore in the future 
very desirable that those now in the business should keep fully 
abreast of the improvements in the art. When a machine or 
process has, after fair trial and investigation, proved to be an 
improvement upon old methods, it is simply suicidal to a busi- 
ness not to employ it. Every new method or contrivance is 
not necessarily an improvement: but the success of small 
tanners and curriers in the future lies solel}^ in the discrimi- 
native adoption of labor-saving machines and time-saving 
processes. 

It is among those who j)roduce leather on a small scale that 
many chemical experiments in depilating, bating, and tanning 
could be conducted without serious loss or inconvenience, and 
it is urgently recommended that in the future more attention 
be given to this subject than it has received in the past. Every 



PREFACE. V 

process or machine used in leather manufacture that has been 
patented in the United States since 1790 to the close of the 
year 1883 is mentioned in this work. Ten volumes of the size of 
the present one would not have been sufl&cient to describe them 
all in full, but a printed copy of any patent issued since the year 
1866 will, on receipt of twenty -five cents, be sent by the Com- 
missioner of Patents to any address in the postal union. The 
patents issued prior to 1866 require to be copied in manuscript, 
and are therefore charged for by the United States Government 
according to the number of words contained in them. Thus 
there is by means of the present volume placed at the disposal 
of any person who desires it, an opportunity to become fully 
acquainted with every step and improvement in leather manu- 
facture made in the United States during nearly a century. 

The author desires to acknowledge the assistance which he 
has received from Dr. Thomas Antisell, Mr. John P. Chapman, 
and Prof. Benjamin S. Hedrick, examiners in the United States 
Patent Office, all of whom have most kindly and willingly aided 
him in many ways. The numerous and valuable lists of patents 
contained in this volume could not have been perfected but for 
the facilities which the above-named gentlemen have extended. 

Prof. William H. Seaman, assistant examiner, early mani- 
fested his interest in the work, and his suggestions from the 
first have proved valuable. 

Col. Weston Flint, and his assistants in the scientific library 
of the United States Patent Office, have also greatly aided the 
author in his researches, and to them also he desires to ac- 
knowledge his indebtedness. 

To the enterprising publishers of this volume much credit is 
due. They have most kindly responded to every suggestion of 
the author, and have cooperated with him in every particular, 
sparing neither time, labor, nor expense. 



VI PREFACE, 

The chernistr}'- relating to leather, skin, and tannins has been 
compiled from the best German and French authorities, and due 
credit is given for all such matter in the proper places in the 
volume. 

It is earnestl}^ hoped by the undersigned that his long labors 
will not prove unfruitful, and that many persons will be bene- 
fited by his work. 

CHARLES T. DAVIS. < 

1114 Pennsylvania Avenue, 

Washington, D. C, Nov. 22, 1884. 



CONTENTS. 



PART I. 
CHAPTER I. 

HJDES AND SKINS — THE VARIETIES OF HIDES AND SKINS USED FOR 
LEATHER — REMOVING HIDES AND SKINS FROM ANIMALS — SELECTING 
HIDES AND SKINS — FRAUDULENTLY INCREASING THE WEIGHT OF 
HIDES — PRESERVING HIDES — LIST OF AMERICAN PATENTS FOR PRE- 
SERVING HIDES-^COMMERCIAL CLASSIFICATION OP HIDES. 

PAGE 

Historical facts relating to the use of Hides and Skins of Animals . 33 

Early facts in regard to flocks and herds as given in the Old Testament . 34 

Cattle breeding in the United States ; the Empii-e of Nature divided 
into three Kingdoms — Mineral, Vegetable, and Animal ; their con- 
nection with the Leather Industry ; the Mineral Kingdom ; the Vege- 
table Kingdom . . . . . . . . . . . 35 

The Animal Kingdom ; the Skins which are applicable to the Manu- 
facture of l^eather ; Historical facts regarding the Manufacture of 
Leather 86 

Surmises as to the manner of the origin of the Art of Tanning . . 37 

Varieties of Hides and Skins used for Leather ; Classification of Tanned 
Leather and of the parts of Hides ; Hides, Kips .... 38 

Skins ; Mammiferous Animals, and their application to the wants of Man ; 
the Common Ox — its Flesh, Horns, Cartilages, Bone, Hair, etc. ; 
Glue ; Effect of the improvement of the Breed of Cattle on their Hides 39 

Hides from UnimproAred Breeds preferred by the Tanner ; Cattle-Skins 
the chief source of supply for Tanneries ; whence procured and the 
Characteristics of those from the Various Countries . . . .40 

Heavy Hides and Medium Weight Hides, Calf-Skins, Sheep- Skins, 
I^amb-Skins whence derived, and Varieties of Leather which they 
produce . . . . . . . . . . . .41 

Sheep and Lamb- Skins, the next in impor'_tance to Ox Hides as sources 
of Leather ; the value of a Breed of Sheep for the Tanner in inverse 
proportion to its value as Wool ; Some of the uses of Sheep and Lamb 
Skins; Goat Skins .......... 42 

Horse Hides, and the Skins of the Ass, Zebra, Quagga, etc. ; Horse 
Leather and the importance of this Industry ; Seal- Skins . . .43 



Vm CONTENTS. 

VAGE 

Hog-Skins, Dog-Skins, Porpoise- Skins, Hippopotamus, and Elephant 
Hides ; Alligator Skins, the Alligator Leather Industry in the United 
States ; Characteristics and Uses of Alligator Leather ... 44 

Kangaroo-Skins and the Leathers which they produce ; Buffalo Hides, 
Deer-Skins, Shark and Rhinoceros Skins, AValrus Hides ; Removing 
Hides and Skins from Animals ........ 45 

Directions urgently recommended in Flaying Hides and Skins ; Import- 
ance of these dii'ections ......... 46 

Selecting Hides and Skins; the Hides of Oxen, Bulls, and Cows; the 
Hides of Animals dying of disease ; Criteria for guiding the purchaser 
in distinguishing the quality of Hides and Skins . . . .47 

Hides of Animals dying from contagious diseases should be rejected or 
handled with great care ; danger of handling such Hides ; Poisoning 
by Bacterium, AntTirax producing Malignant Carbuncles : Disinfecting 
I'anneries and other places where Skins are stored ; Importance of 
thorough Cleansing of the Store-room ...... 48 

Fraudulently increasing the Weight of Hides by the employment of Sul- 
phuric Acid ; Tests for the Detection of this Fraud ; Preserving Hides ; 
Mode of Salting ; Delane's Method the one generally employed . 49 

Quantity of Salt required; Glauber's Salt for Salting Hides; Other 
Materials for Preserving Hides ; Moret's Composition for Impregnating 
Hides and Skins and Preserving them so as to be capable of being 
unhaired by a simple immersion in water ...... 50 

The Preparation and Application of Moret's Composition . . .51 

Advantages claimed for Moret's Composition ; Rock's Liquid for Curing 
Hides 52 

Sabath6 and Jourdan's Process ; Napier's Process, Sacc's Process, 
Wickersheimer's Process ......... 53 

List of all Patents issued by the Government of the United States of 
America for Preserving Hides from 1790 to 1883 inclusive ; Commercial 
Classification of Hides ; Dry Flint ; Dry Salted ; Green Hides . . 54 

Green Salted Hides ; Part Cured Hides ; Damaged Hides ; Glue Stock ; 
Branded Hides ; etc. . . . . . . . . .55 



CHAPTER IL 

SYNOPSIS OF THE HISTORY OF TANNING — COMMERCIAL VARIETIES OF 

LEATHER. 

Synopsis of the History of Tanning ; Conditions upon which an Art must 
rest in order to improve ; Facts in reference to the history of Leather 
derived from the Old Testament ....... 5C 

Colored Leather described by Ezekiel as early as 593 B. C. as in use 
by Babylonians, Chaldeans, Pecods, Shoas, Koas, and all the Assyrians ; 
Testimony of Herodotus in regard to the use of Leather; Early use 



CONTENTS. IX 

PAGE 

of Leather by the Greeks, Phoenicians, Germans, and Britons ; Testi- 
mony of Homer and Hesiod ........ 57 

Early expressions regarding the use of Leather ; the legend of St. Crispin ; 
the names of the early discoverers and improvers of the Processes of 
Tanning Leather ; Discoveries of MacBride (1768), Seguin (1 795), and 
Banks (1801); MacBride's Process of Raising by Sulphuric Acid; 
Seguin's Method by which Hides and Skins were Tanned in a shorter 
time, and Banks's discovery of the Tanning Property of Terra Japonica 

(Catechu) 58 

The English discovery of the Art of Varnishing Leather ; the introduction 
of the art of preparing AVater-Proof Leather by Ballamy, Von Hilde- 
brandt, Edward, and others ; Little done by science in regard to the 
Improvement of the Art of Tanning ; Great improvements made in 
Apparatus, especially in the United States ..... 59 

Skill not force, Chemical Knowledge not steam power, which in the 
future must cheapen and accelerate the Process of Tanning ; our in- 
ventors must aim to be good Chemists, as well as good Mechanics ; 
Room for inquiry after Tanning Materials and as to the Hide itself 
and its Structure .... ...... 60 

The System of Tanning or Tawing by means of Chromium Compounds 
by Dr. Heinzerling in Germany ....... 61 

The claims of Dr. Heinzerling as to the meritorious and original features 
of his Process ; Experiments of David Kircaldy, London, on Bark- 
Tanned and Chrome Leather ; Advantages which seem to be offered 
by the Chrome Process . . . . . . . • .62 

Localities in which Dr. Heinzerling's Process, is in use ; Not yet full}' 
passed critical stages of practical experiment ; Commercial varieties 
of Leather ; Characteristic properties of Leather ; Leather Chemic- 
ally considered .......... 63 

Tawing and the class of Skins to which it is applied ; Tawing practised 
by the Romans ; Introduced into Hungary in the 1 2th Century ; 
Chamois Dressing invented in Hungary ; the Hungarians celebrated 
in early times for their White Leather ; French and Dane's Leather 
made from Lamb and Goat- Skins for the manufacture of Kid Gloves . 64 
Red or Bark Tanning the oldest Method of Tanning ; Leather similar to 
Morocco and Cordovan made by the Ancient Orientals ; Persian and 
Babylonish Leather ; the art of making Leather brought from Asia 
into Europe ; the Turks, Russians, and Hungarians, the most cele- 
brated Tanners in the first centuries of the Christian era ; Cordovan, 
Morocco, Shagreen, and Russia Leather ...... 65 

The Morocco Leather Industry in the United States ; Decline of the 
Morocco and Chamois Leather Industries in Russia; the Tanning- 
Industry in Russia . . . . . . . . . .66 

Shagreen and Russia Leather . . . . . . . .67 



X CONTENTS. 



Hungarian Leather ; Parchment ; Artificial Parchment ... 68 

The use of Parchment, and where most hirgely produced ; Alum Leather ; 

JBazil ; BufF Leather ; Chamois, Shammy, or Shamoy Leather ; 

Enamelled Leather . . . . . . . . . .69 

Enamelled Leather first manufactured in the United States in Newark, N. 

J. ; Fair Leather ; Juncten ; Japanned, Patent and varnished Leathers 

first made in the United States at Newark, N. J.; Oil Leather; 

Roan; Russet; Saffian Leather ; Mogador Leather ; Skiver . . 70 
Split Leather ; Wash Leather ; Whang ; White Leather or Tawed 

Leather; List of names applied to Leathers in Commerce . . 71 

Artificial Leather and its uses ; Vegetable Leather . . . .7? 

Artificial Leather produced in Boston, Mass.; Importance of the Leather 

Industry in the United States ........ 73 

^ CHAPTER IIL 

STATISTICS OF THE TANNING INTERESTS IN THE UNITED STATES. 

Statement of the number of Tanneries in the United States ; Capital ; 
Hemlock and Oak Bark used ; Hides and Skins Tanned and the 
total value of products for the year 1880 . ... . . .74 

The leading States engaged in this Industry . . . . . .76 

Increase of Tanneries in Virginia, Tennessee, and other Southern States ; 
Exports and Imports of Leather ; the Leather Industry in Italy . 77 

The Leather Industry of the United States rivals those of England, 
Germany, and Austria, and our exports should be largely increased ; 
Objections of English Tanners to our Leather ..... 78 

Imports and Exports of Hides, Skins, Bark for Tanning, Cutch, and 
Gambir, Tallow, Fish Oils, etc., into and out of the United States for 
the twelve months ending June 30, 1882, and June 30, 1883, respec- 
tively ; Number of Leather Currying Establishments in the United 
States and their product in 1880 ; Importance of this Industry in 
Massachusetts . . . . . . . . . . .79 

Table of the Leather Currying industry of the twelve leading States, 
representing nine-tenths of the whole business ..... 80 

CHAPTER IV. 

EXAMINATION OE LEATHERS. 

Importance of the determination of the value and quality of Leather by 
chemico-technical examination; Marquis's Method — 1. Determination 
of fat and resin . . . . . . . . . .81 

2. Determination of Lime in Leather. 3. Determination of the Tan- 
ning constituents : Method proposed by Heinzerling ; Determination 
of AVater ; Percentage of Ash ; Importance of determining the amount 
of Lime in Leather . . . . . . . . . . 82 



• CONTENTS. XI 

PAGE 

Percentage of Fat . . . . . . . . . .83 

To determine the Sebaoie Acid ; Determination of Nitrogen ; Plan pro- 
posed by Muntz; Barrentrapp-Will Method ; Cori'in, formulae of Reimer 84 

Tanning Substance. 1. Tannic Acid ; Defects of Marquis's Method for 
determining Tannic Acid ; Mittenzweig's Method. 2. Mineral Con- 
stituents ; Determination of Mineral Materials in Mineral Tanned 
Leathers of Knapp and Heinzerling ; Examination of the cutting sur- 
face of leather, as a criterion ; Behavior of Tanned Leather toward 
boiling water as a test . . . . . . . . " . 85 

Determination of means used to increase the weight of Leather ; Detec- 
tion of Adulterations, such as Glucose, added for this purpose ; Physi- 
cal methods of testing Leather ........ 86 

I. Change in volume and ability for resisting water ; Table of Dr. Hein- 
zerling in regard to the comparative resisting qualities of Tanned 
Leather and Heinzerling' s Mineral Tanned Leather . . . .87 

Results shown by the Table ; IL Testing the strength of Leather ; 

AVeiner's Apparatus . ... . . . . . 89>' 

Tables showing the strength of a Skin in different places ... 91 



PART II. 
CHAPTER Y 

ANIMAL SKIN. 



The Raw Products with which the Tanner has to deal — 1. Hides and 
Skins. 2. Tanning Materials ; the construction of Animal Skin ; the 
Ejjidermis and its Composition ........ 93 

The Epidermis does not combine with Tannin, and is, therefore, useless 
to the Tanner ; the Corium or Leather Skin ; the Quality of the 
Leather dependent upon the thickness, flexibility, and strength of the 
Corium ; Coriin ; Illustration showing an enlarged Transverse Section 
of the Skin 94 

Chemical Process in the production of Glue ; Skin slowly and completely 
dried in the air can be kept for a long time ; Decomposition of Moist 
Skins ; Preservation of Skins with Salt, . or Immersed in Strong 
Brine ; the Chemical and Morphological Constitution of Skins as shown 
by RoUet and Reimer ......... 96 

Modes of Preparing Coriin ; to obtain perfectly pure Coriin free from 
an admixture of Cell Elements . . . . . . .97 

Behavior of Coriin toward different Substances ; Liming contliuied too 
long gives poor weight ; Composition of Coriin ; Connective Tissue 
Substance and the Intercellular Substance, the difference between . 98 



Xll CONTENTS. 

PAGE 

To prepare Connective Tissue Substance ; Behavior of Connective Tis- 
sue Substance towards various other Substances .... 99 
The Swelling Property of Skin Fibre 100 

CHAPTER VT. 

VEGETABLE TANNING MATERIALS. 

Section I. Tannix or Tannic Acid ; Tannin or Tannic Acid ; 
Great variety of Plants in which Tannic Acid occurs . . . .100 

The different varieties of Tannin, their Chemical and Physical behavior, 
and whence derived .......... 101 

Classification of Tannic Acids by E. Wagner into physiological and 
pathological Tannic Acids ; -whence these Tannic Acids are derived ; 
Wagner's views on the Subject of Leather Tanned with the respective 
Tannic Acids ; our knowledge of the different Tannic Acids still in- 
complete ; Principal obstacles to a determination of the Nature of 
Tannic Acids 102 

Gallotannic Acid — Tannin of the Xut-gall ; Discovered by Lewis in the 
Eighteenth Century; Pelouze's Process for its Examination; Appa- 
ratus of Robiquet and Boutron . . . . . . . . lOo 

Process of Mohr for the Exhaustion of Gall-nuts . . . . .104 

Appearance and Qualities of the Tannin ; Domine's Process for the ex- 
haustion of Gall-nuts ; Separation of the Tannic Acid by the Aqueous 
Solutions of Sulphuric and Hydrochloric Acids, etc. ; Melting and de- 
composition of Tannin ......... lOS 

Behavior of Tannin under various conditions ; Tannin considered by 

Sti'ecker a Glucoside . . . . . . . , .106 

More recent Experiments prove Tannin not to be a Glucoside ; Experi- 
ments of Rochleder and Kawalier ; Liebig on the Transformation of 
Tannin into Gallic Acid by means of Potash and thence into Carbonic 
and Pyrogallic Acids ; Behavior of Tannin toward various Substances 107 

Jmpure Tannin Substances modify themselves when kept in contact with 
the Air ; Constituticni of Gallotannic Acid ; Experiments of Strecker 
and Schriff ; Conclusions of SchrifF; Schriff's formula of Tannin . 108 

The new formula of Tannin confirmed ; Tannomelanic Acid ; how ob- 
tained ; Tannopinic Acid . . . . . . . . .109 

Tannoxylic or Ptufitannic Acid ; Quercotannic Acid ; Properties and 
Behavior of Quercotannic Acid. . . . . . . .110 

Quercus Red ; Quercus Bitter or Quercin . . . . . .111 

Querphlobaphene ; Phloroglucin ; Protocatechuic Acid ; Pyrocatechin ; 
the property in Tannic Acid of forming insoluble combinations with 
Alkaline Salt ; loss of Tannic Acid in using Hard Water ; Fermenta- 
tion of Tannic Acid by Fungi - and P'erments ; Filtering of Water 
through exhausted Tan ; Researches of Sclmlze in regard to the Tan- 
nic Acid yielded by Oaks of different ages . . . . .112 



CONTENTS. Xlll 

PAGK 

Tannic Acid generally present in the Roots, Barks, and Branches of 
Trees ; Tannic Acid a Brimary product of Vegetable Life ; Action of 
the different Tannic Acids toward the Corium or Leather Skin ; Tan- 
nic Acid which when heated forms Byrogallic Acid, furnishes 
Leather less capable of resisting Water than Tannic Acid yielding 
Pyrocatechin ; Influence of Extractive Substances upon the value of a 
Tannic Acid; Influence of Resins, Pectine Substances, etc. . .113 

Spxtion IL Vegetable Tanning Materials .... 113 

Rutea ; Kino ; African Kino, Malabar or East Indian Kino ; Kino very 
rich in Tannic Acid ; Garabier, its percentage of Tannin high ; Cate- 
chu or Terra Japonica ; its Constituents, Qualities, and Adulterations; 
the Leather produced from Catechu ; Gall-nuts — the richest in Tan- 
ning of all Tanning materials, their formation and qualities . .114 

Green Galls ; European Galls ; Chinese Gall-nuts ; the countries in 
which Gall-nuts are produced ; Rove or Bassora Gall-nut . . .115 

Sumach ; different varieties of Sumach found in Commerce — Sicilian, 
Italian, Spanish, Tyrol, French, and American Sumachs . . .116 

Swedish Sumach ; the Tannic Acid contained in the Sicilian Sumach 
according to Stenhouse identical with Gallotannic Acid ; Tannic Acid 
of Old Sumach ; Leather prepared with Sumach possesses but little 
capacity of resisting Water ; Valonia ; Qualities of Leather prepared 
with Valonia ; Divi-divi ; Qualities of Leathers Tanned with divi-divi ; 
Tannic Acid of divi-divi ; Myrobalans . . . . . .117 

Bublah ; Logwood ; Fustic ; Weld ; Larch Bark ; Fir Bark ; Hemlock 

Bark; Qualities of Hemlock Bark . . . . . . .118 

American Hemlock Extract; Oak Barks; Walnut Bark; Lombardy 
Poplar Bark; Elm Bark 119 

Horse-chestnut Bark ; jEsculotannic Acid ; qualities, constitution, and 
behavior of ^li^sculotannic Acid ; Horse-chestnut Extract ; AVillow 
Bark 120 

Alder Bark ; Beach Bark ; Protaceae Barks ; Snouba Bark ; Scorza 
Rosa; Ratanhy Root 121 

Avens Root ; Tormentil Root ; Sassafras Root ; Live Oak Wood ; Que- 
bracho ; Mimosa . . . . . . . . . . 122 

Table showing the percentage of Tannin contained In the various Tanning- 
materials determined according to different methods . . . .123 

Results of more recent examinations of various substances containing 
Tannin, according to Fraas . . . . . . . .124 

Tanning materials used in most countries only such as are there produced 
in great abundance ; the Tanning materials used in principal countries ; 
Practical experiments show that there is a considerable difference in 
the quiintity of the various Tannins absorbed by the Skin; Table of 
the quantities of Tannin required, according to Anthon, for the con- 
version of each one pound of Skin into Leather .... 125 



XIV CONTENTS. 

PAGE 

Table of Experiments ; Experiments by Kester showing the increased 
weight of Hides after Tanning ........ 126 

Tables of Experiments of Prof. Miintz and Dr. Schon regarding the ab- 
sorption of different Tannins by the Skin, and of the removal of resi- 
nous extractive substances in Leather Tanned with different Tannins ; 
Conclusions of Miintz and Schon regarding the value of Leather . 127 

Tables showing the results of the experiments of Miintz and Schon on the 
percentages of Skin and Tannin in various kinds of Leather, as well 
as of Glue, Tannin, and Nitrogen in Leather perfectly dry and free 
from all soluble substances . . . . . . . . 1 28 

Table of the number of pounds of Leather free from Resin obtained from < 

220 pounds of Dry Skin ; Results to be deduced from these Experi- 
ments as to the quantities of different Tannins absorbed by Skins . 129 

CHAPTER YII. 

MINERAL AND ARTIFICIALLY PREPARED TANNING SUBSTANCES. 

Section I. Mineral Tanning Materials ; Use of Mineral Tanning 
materials in very early times ; Principal Mineral Substances to be con- 
sidered — 1. Alum, Aluminium Sulphate, and Aluminium Acetate. 2. 
Chromates and Chromic Oxides. 3. Ferric Salts. 4. Common Salt ; 
Aluminium Sulphate; Preparation, qualities, and characteristics . 130 

Aluminium Sulphate in Tanning ; Alum ; Preparation, qualities, and 
characteristics . . . . . . . . . . .131 

Iron Alum ; Manganese Alum ; Chromium Alum ; Alum in Tanning ; 
Aluminium Acetate ; Preparation, (jualities, and characteristics . 132 

Chromium Salts ; Potassium Bichromate in Tanning ; Preparation, 

qualities, and characteristics ........ 133 

Sodium Bichromate ; Calcium Bichromate ; Strontium and Barium ; the 
Neutral Alkaline Chromates; Chromium Alum, its use in Tanning ; 
Chromic Sulphate . . . . . . . . . .134 

Ferric Salts ; Recommendation of Ferric Salts for Tanning by D' Arcet 
in the last century; Patent of Bordier in 1842 ; Experiments of Pro- 
fessor Knapp on Tanning with Ferric Salts; Knapp's L-on Soap; 
Common Salt, its use in Tanning . , . . . . .135 

Section II. Artificially Prepared Tanning Substances; Jen- 
nings's Artificial Tanning Material . . . , . . .136 

Sky's Tanning Material; Lees's Artificial Tannin; an Artificial Tannin 
formed by heating a solution of Resins and Camphor with Sulphuric 
Acid 137 

The Classes to which the different Artificial Tannins belong . . . 138 



CONTENTS. XV 



CHAPTER VIII. 

CHEMICAL EXAMINATION OP VEGETABLE TANNING MATERIALS. 

PAGE 

Method of determining the Tannic Acid ; Substances found by Gerber 
in a solution of the inner layer of Oak Bark ; Davy's Volumetric 
method of analysis .......... 139 

Miintz and Rampercher's Apparatus for Filtering Tanning Liquor under 
pressure ............ 140 

Fleck and Wolf's Method; Persoz's Method 141 

Wildenstein's Colorimetric Method ; Fehling's Method modified by G. 

Muller 142 

Satisfactory results secured from the last-named method according to 
Gauhe and Hallwachs ; Lippowitz employs Isinglass in place of White 
Glue for precipitation of the Tannic Acid in the Felling-Miiller 
Method; Carpene-Barbieri's Method ...... 143 

Gerland's Method ; Jeans's Method ; Hammer's Method . . . 144 
Table of the relation between the Specific Gravity and the Percentage of 
Tannic Acid, intended to facilitate calculations when Hammer's Method 
is employed; Franz Schulze's modification of Hammer's Method . 145 
Salzer on Schulze's modification ; Observations on the manner of exe- 
cuting Hammer's Method ......... 146 

Special Areometers which can be used to advantage with Hammer's 

Method; Mittenzwei and Terreil's Method 147 

Manner of executing this method . -, . . . . . . 148 

Hallwachs states that the results of this method are too high ; Grassi's 

Method 150 

Wagner's Method 151 

Biichner's Remarks on Wagner's Method . . . . . .152 

Neubauer's Criticisms on Wagner's Method ; Clark's modification of 
Wagner's Method . . . . . . . . . .153 

Loewenthal's Method modified by Neubauer ; Details of the execution of 
this method . . . . . . . . . . .154 

Making the Titre . .156 

Loewenthal's modification of his method; Kathreiner on the manner of 
executing Loewenthal's Method ....... 157 

Results of experiments by Kathreiner on the Tannic Acid in Tanning 
materials ............ 158 

Recommendations of Kathreiner ; Examination of Oak Bark . . 159 

Practice of Neubauer and Kathreiner . . . . . . .160 

Results obtained by Cech and Neubauer . . . . . .162 

Comprehensive comparison of the results obtained by the above-described 
methods . . . . . . . . . . . .163 

Table by Hallwachs showing the difTcrence in the percentage of Tannic 
Acid determined according to the methods of Fehling, Muller, Loewen- 
thal, Hammer, Fleck, and Mittenzwei . . . . ... 164 



XVI CONTENTS. 

CHAPTER IX. 

WATER. 

PAGE 

Section I. General Remarks Concerning Water . . .165 
Determination of the qualities of Water for Tanning purposes . . 1(36 
The effects of Hard and Soft Watei's when used for Soaking, Cleansing, 
and Washing the Hides ; Eitner's Experiments regarding the effects of 
inorganic constituents of Water upon the depilated Skin ; Comparative 
effects of Hard and Soft Waters in Swelling or Plumping Hides ; tem- 
perature of Water for Preparing Hides . . . . . .167 

Importance of a Uniform Temperature in the Water used in a Tannery ; 

Supply of Water to a Tannery . . . . . . . .168 

Section II. Methods for Determining the Constituents of 
Water; Qualitative Examination of Water ..... 169 

Clark's Process of Determining the Hardness of Water by Soap Solu- 
tion ; Mode of Execution of Clark's Process according to Faisst and 
Knauss . . . . . . . . . . . .170 

Determination of total Hardness . . . . . . . ^ . 1 ? 1 

Determination of permanent Hardness . . . . . . .173 



PART HI. 
CHAPTER X. 

BARK — THE NATURE OF BARK — TOOLS USED IN BARKING — ROSSING 
BARK — LIST OP AMERICAN PATENTS FOR BARK-ROSSING MACHINES 

PREPARING BARK FOR TRANSPORTATION LIST OF AMERICAN 

PATENTS FOR PREPARING BARK FOR TRANSPORTATION. 

The Nature of Bark ; the Epidermis . . . . . . .174 

Davy's Examination of the Epidermis of the Bamboo, the Sugar Cane, 
etc. ; the Parenchyma ; the Epiphloeum ; the Mesophlceum ; the Lieber 
or Endophloeum ; the Cortical Layers ; the Alburnum or Sap-wood . 1 75 
Peeling the Bark and the most convenient time for it . . . .176 

Davy on the comparative amounts of Tannin in Oak Bark cut in the 
Spring and Fall ; Influence of seasons and place at the time of Bark- 
ing in the richness of Tannin ; Tools used in Barking . . .177 
Daigneau's Contrivance for Cutting Bark preparatory to Peeling . .178 
Rossing Bark . . . . . . . . . . .181 

List of all Patents for Bark Rossing Machines issued by the Government 
of the United States of America from 1790 to 1883 inclusive; Pre- 
paring Tanned Bark for Transportation ; Process 'of William H. Smith, 
of Chicago, Illinois . . . . . . . . . .182 



CONTENTS. XVll 

PAGE 

List of all Patents for Methods and Machines for Packing Tan Bark 
for Transpoi'tation issued by the United States of America from 1790 
to 1883 inckisive 183 

CHAPTER XL 

GRINDING, CUTTING, CRUSHING, AND CONVEYING TAN BARK — LIST OF 
AMERICAN PATENTS FOR BARK MILLS. 

Si-.CTiON I. Grixding, Cutting, and Crxishing Tan Bark; 
Importance of the Grinding and Leaching of Bark ; Prime Require- 
ments of a good Bark Mill . . . . . . . .184 

Some of the peculiarities of the present Bark Mills ; Improvement of the 
Troy or Starbuck Bark Mill ; the Horizontal Cylinder Breaker Bark 
Mill manufactured by C. Weston & Sons, Salem, Mass. . . . 185 

Mosser's Safety Coupling Device for Bark Mills .' . . , .186 

Barber's Bark Mill 188 

Thompson's and Johnson's improved Bark Mill . . . . .190 

List of all Patents for Bark Mills issued by the (Government of the United 

States of America, from 1790 to 1883 inclusive. . . . .19.5 

Process for preparing Tan Bark for use, which consists in crushing the 
Dry Bark and reducing it to thin Hakes by passing it between rollers 
under heavy pressure after it has been ground; Holbrook's Machine 
for breaking up the cellular structure of Bark . . . . .197 

Section II. Improved Bark Conveyer; Zane's Bark Conveyer . 200 

CHAPTER XII. 

LEACHING TAN BARK — THE KINDS OF LEACHES EMPLOYED — BUILDING 
ROUND LEACHES — PILLING AND RUNNING THE SPRINKLER LEACHES 
— THE '^ BARKOMETER" — PURIFYING EXTRACTS OF BARK — OBTAIN- 
ING TANNIC ACID IN ACICULAR FORM LIST OF AMERICAN PATENTS 

FOR PROCESSES AND APPARATUSES FOR LEACHING AND MAKING EX- 
TRACTS OF TAN-BARK. 

Section I. The Kinds of Leaches Employed ; Best Method of 
Leaching or Extracting Tannin from Tan Bark long sought for ; the 
Lixiviation commonly conducted by one of three methods ; the Sprink- 
ler Leach invented by Allen and AVarren ...... 203 

The forms, materials, and modes of constructing Leaches ; Apparatus for 
the Automatic Distribution of Fluids for Leaching, and to render the 
distribution uniform .......... 204 

Leach with the Allen and Warren Hanging Sprinkler attached . . 208 

Section II. Building Round Leaches . . . , . 209 

Rule by which to find the capacity in cubic feet of a Leach of any size; 

Table showing the capacity of Round Leaches of many sizes . .212 

The Supply Tank of a Leach ; a Round Tank the cheapest and most 
durable; Straining the Liquors going to the Leaches . . . 213 

B 



XVlll CONTENTS. 

PAGE 

A Supply Tank in -which both direct and exhaust steam are used . . 214 
liegulating the Sprinklers ; Diiferent modes of heating the Tank . .215 
Making and working of box suitable for exhaust steam . . .216 

Regulating the supply of exhaust steam ; Wooden Conductor to Leaches, 
described and illustrated . . . . . . . . .218 

Section III. Filling and Running the Leaches . . . 219 
Liquor denser than Water is inferior Leaching Fluid ; the quantity of 
Liquor yielded by a cord of Ground Hemlock Bark, when Water is 
used as the Leaching Fluid ........ 221 

Yields of Oak and Chestnut Barks ; Using old or weak liquors for the 
Leaching Fluid ; the best way to concentrate the strength without '• 
doubling ; Temperature of the liquor when it commences to run from 
the leach ; the strongest liquors obtained with the least heat . . 222 

Amount of liquor yielded under certain conditions ; Gum in liquors ; 
Time required for Leaching by Hot-water Method ; Advantages of 
Allen and Warren's System when it is desired to take from the Bark 
the larger portion of its Tannin with the use of little or no heat ; the 
liquors obtained by this system very clear and pure . . . . 223 

Sizes and arrangement of Leaches . . . . . . . 224 

On the amount of Ground Bark obtained from a cord of Bark as pur- 
chased . . . . . . 225 

Section IV. The Barkometer ....... 226 

Section V. Purifying Extract of Bark ; Bradley's Apparatus 
for the removal by precipitation of the resinous gums and floating par- 
ticles of Bark from the extract emanating from Leach Tubs . .227 
Essential elements of this process; Description of Bradley's Apparatus; 

McKenzie's Screw form of Evaporator ...... 230 

Section VI. Obtaining Tannic Acid in Acicular Form ; 

Holtz's Apparatus for improvement in the production of Tannic Acid 232 
List of all Patents for Processes and Apparatuses for Leaching and 
making extracts from Tan Bark issued by the Government of the 
United States of America from 1790 to 1883 inclusive . . . 235 



PART IV. 
CHAPTER XIII. 

WASHING AND SOAKING HIDES AND SKINS — PROCESSES FOR SOFTENING 
HIDES, SKINS, AND PELTRIES — LIST OF AMERICAN PATENTS FOR 
COMPOUNDS FOR SOFTENING HIDES — PROCESS FOR PLUMPING BEFORE 
DEPILATING. 

Section I. Washing and Soaking; Soaking of Green Hides and 
Dry Hides; Selecting Hides according to size, variety, thickness, and 
condition . . . . . . . . . . . .237 



CONTENTS. XIX 

PAGE 

Injuries which result to Hides in Soaking ...... 238 

Hammond's Process of Soaking Hides with Saltpetre or Nitrate of 
Potassa; Principle upon which this manner of Soaking is based; 
Practical details of the process ........ 239 

Advantages claimed for this process ....... 240 

The practice of Soaking small Hides or Kips in foul bloody water ; Soft- 
ening by Sweating ; Softening Imported Salted Hides ; a difference in 
the practice of different .Tanners in Soaking ; Dry Hides Soaked 
longer and handled oftener than Green Hides . . . . .241 

Soaking Hides after being worked in the Hide Mill ; the practice in some 

parts of Prance of Soaking Dry Hides in Lime-water . . . 242 

Soaking Dry Hides in Running Water ...... 243 

Section II. Processes for Softrnixg Hides, Skins, and Pel- 
tries; Softening Dry Hides, Skins, and Peltries by Soaking them 
in the waste water from Gas Works ....... 243 

Advantages claimed for this system ; Barron's process .... 244 

Berry's Process for Softening Hides . . ■ . . . . 24.'> 

List of all Patents for Softening Hides issued by the Government of the 

United States of America from 1790 to 1883 inclusive . . . 246 

Section III. Process for Plumping before Depilating, and 
THE Treatment op Hides or Skins with an Acid Solution 
before Liming, for thk Removal of Salt or other Mat- 
ters ; Ely's Process for Plumping Hides before Depilating; Practical 
details of the process . . . . . . . . .246 

Advantages claimed for Ely's Process . . . ■ . . . . 249 

CHAPTER XIY. 

HIDE MILLS — LIST OP AMERICAN PATENTS FOR HIDE MILLS — LIST OF 
AMERICAN PATENTS FOR BREAKING HIDES. 

The Softening of Dry Hides and Skins in the Hide Mill after removal 
from the Soaks ; Difference in the forms of Hide Mills for the various 
branches of Leather Manufacture; Practice of the Morocco 1'anners 
at Lynn, Mass., and other parts of Xew England .... 250 

Practice of the Morocco Tanners of Philadelphia, Pa. . . . .2.51 

Hide Mills in common use ; the Hide Mill Invented by Wm. Edwards of 
Northampton, Mass., in 1812; Edwards's invention of the contrivance 
for rolling Sole Leather ; the Idea of a Hide Mill primarily due to the 
Fulling Machine ; great antiquity of the Fulling Process ; Detailed 
description of a Hide Mill ........ 959 

Friend and Annable's improvement in connec^tlng the Pitman which actu- 
ates the Beaters In Hide Mills, with detailed description . . . 253 
Mill for Softening Hides and Fulling Cloth, with detailed description . 256 
Middleton's Hide Mill, with detailed description 258 



XX CONTENTS. 

PAGK 

List of all Patents for Hide Mills, issued by the Government of the 
United States of America from 1790 to 1883 inclusive . . . 260 

List of all Patents for Breaking Hides, issued by the Government of the 
United States of America from 1790 to 1883 inclusive . . . 261 

CHAPTER XY. 

PROCESSES AND COMPOUNDS FOR DEPILATING HIDES AND SKINS — THE 

LIMING PROCESS — OTHER DEPILATORY COMPOUNDS AND PROCESSES 

DEPILATING BY SWEATING — THE COLD SWEATING PROCESS — THE 
WARM SAVEATING PROCESS — OBSOLETE METHODS OF DEPILATING — 
LIST OP AMERICAN PATENTS FOR COMPOUNDS FOR DEPILATING HIDES 
AND SKINS. 

Section I. The Liming Process ; Depilation generally done by the 
use of Lime ; Objections to the Liming Process . . . .261 

Harshness and Brittleness imparted to Leather by Liming ; Restoration of 
Suppleness to Leather by Bating ; Some of the inconveniences of the 
Liming Process . . . . . . . . . .262 

Eflbrts to Substitute Other Agents ; Preparation of Hides for Liming . 263 

Precautions to be taken in Liming ; Treatment of Calf-skins in the Limes ; 

Salted Calf-skins 264 

Replacing Lime in Depilating by Acid Liquors requires judgment ; 
Lime Vats ; Liming SjDlit Hides ; Determination of the Quantity of 
Lime in a Vat .......... 265 

The number of Vats in a Series ; the use of Old Limes ; the time em- 
ployed for Liming ; the Keel for Handling in the Lime Vats ; Stein- 
mann's Apparatus for Handling Hides in the Lime Pits, detailed 
description ........... 266 

Study's Rotary Rack for Liming Hides ...... 269 

Section. II. Other Depilatory Compounds and Processes ; 
Robinson's Process ; Ward's Process ...... 269 

Wilson's Process; Carter and Keith's Process; De Montoison's Pro- 
cess ; Head's Process ; Banks's Process of Depilating with Steam in a 
Tight Room or Vat 270 

Eaton's Process of Depilating by the use of Soda Ash, Caustic Lime, 
Monosulphuret of Potassium, Hard Soap and Soft Water . . 271 

Schlosser's Composition for Depilating Green and Dry Hides with Nitrate 
of Potassa, Chloride of Sodium, Sulphuric Acid and Tartaric Acid . 272 

Adler's Compound consisting of Sulphuretted Hydrogen Gas in connec- 
tion with Lime, Soda Ash, etc., as a Dejiilatory and for the purpose 
of Swelling Hides 273 

Henry's Compound of Potash, Lime, Salt, and Sulphur, and Charcoal 
for Depilating . . . . . . . . . . . 274 

Siebel's Application of "Refuse Gas-lime" as a Depilatory; Proposal 
of Boettger to use as a Depilatory Lime that had served for Purifying 
Gas . 275 



CONTENTS. XXI 

• PAGE 

Watteau's Compound of Double Sulphate of Sodium and Calcium for 
Depilating; the Patents of Brainard, Claus, and Lynds • . . 276 

Anderson's Process of Depilating with Cha,rcoal ..... 277 

Maynard's Method for Depilating by the employment of Lime in Water, 

' together with Sulphurous Acid ; Mower's Process of the combination 
of Lye from Wood Ashes or Potash, and Lime which has been treated 
by the Gas generated by Sulphuric Acid ; Sulphuret of Lime and 
Water, for Unhairing Hides and Skins, and for Pulling Wool . .278 

Advantages claimed for this Process ....... 280 

Tinnerholm's Process of Depilating and Removing Grease, with a com- 
pound of Water, Lime, Soda Ash, Saltpetre, and Flowers of Sulphur ; 
Advantages claimed for this Process . . . . . .281 

Foley's Process of Softening, Plumping, and Depilating Hides and 
Skins through the employment of Sulphide of Barium, in solution . 282 

Advantages claimed for this Process ; Patents for the use of Sulphide or 
Sulphuret of Calcium for Depilating; Use of Sulphide of Calcium 
for this purpose in Europe and America ; Action of Sulphur com- 
bined with Lime .......... 283 

Depilating with a compound of Water, Burnt Oolite, and Muriatic 
Acid ; BoUman's Process of Depilating with a mixture of Water, 
Lime, and Blood .......... 284 

Advantages claimed for this Process ; Proposed Bating mixture of Blood 
and Ammonia . . . ... . . . . . . 285 

Laure's Process of Depilating with Water in an open vessel . . . 286 

Advantages claimed for this Process ; Process of Depilation by Sul- 
phuret of Calcium and Soda . . . . . . . .287 

Potash, Lime, and Orpiment as a Depilatorj^ ; Boettger's Pi'ocess of 
Depilating by the Hydrosulphate of Lime ; Preparation of the 
Hydrosulphate of Lime . . . . . . . . ' . 288 

Boudet's Process of Depilation by Caustic Soda ..... 290 

Section III. Depilating by Sweating; Cold Sweating Process 
much used in New York, New Hampshii'e, and Northern Pennsyl- 
vania 291 

Mason's Building for Sweating Hides and Skins, with detailed de- 
scription ............ 293 

Advantages claimed for this Building . . ..... 295 

Care to be observed in Sweating Hides ...... 296 

The Warm Sweating Process largely employed in Germany and other 

parts of Europe . . 298 

Sweating Fresh Hides . . .' 299 

Section IV. Other Methods of Depilating now nearly obso- 
lete ............ 300 

Raising by Sour Tan Liquor ........ 301 



XXll CONTENTS. 

PAGE 

Raising by Yeast ; List of all Patents for Compounds for Depilatino; 
H'des and Skins issued by the Government of the United States of 
America from 1790 to 1883 inehisive ...... 302 

CHAPTER XVI. 

UNHAIRING AND FLESHING — UNHAIRING BY THE HAND PROCESS 

rr-ESHlNG BY THE HAND PROCESS — SOAKING HIDES AFTER FLESHING 

UNHAIRING AND FLESHING BY MACHINERY LIST OP AMERICAN 

PATENTS FOR UNHAIRING AND FLESHING MACHINES. 

Section I. Unhairing by the Hand Pkocess ; the Beam House ; 
■with the forms of Beams employed; the German form of Beam and 
Stand used in Tawing Establishments, and the Unhairing Knife ; 
Practical details of the Unhairing Process . . . . .304 

Section II. Fleshing by the Hand Pkocess ; the Fleshing Tools 308 

Section III. Soaking Hides after Fleshing .... 311 
Soaking Hides in a Steeping Cistern after Fleshing, as practised in Ger- 
many and France ; how long should the hides soak after Fleshing, 
and what indicates their readiness for Scouring ? . . . .312 

Section IV. Unhairing and Fleshing by Machinery ; the Un- 
hairing of Hides and Skins by Machinery now an accomplished fact 313 
Larrabee's Unhairing Machine with detailed description . . . 314 

Tapley's Unhairing Machine with detailed description . . . .318 

McDonald's Unhairing Machine with detailed description . . . 322 

McDonald's improvement in Feed Rolls for Unhairing Machines . . 325 

Taylor's Machine for Unhairing, Fleshing, and Working Hides and 
Skins, with detailed description ....... 327 

Janson's Machine for simultaneously Unhairing and Fleshing Hides and 
Skins, with detailed description ....... 330 

Roberts and Lenox's Fleshing, Slating, and Striking Out Machine . 332 
List of all American Patents for Unhairing Machines issued by the 
Government of the United States of America, from 1790 to 1883 
inclusive ............ 333 

List of- all Patents for Fleshing Machines issued by the Government of 
the United States of America, from 1790 to 1883 inclusive . . 334 

CHAPTER XVII. 

BATING AND FINAL PREPARATION FOR THE OOZE — BATING COMPOUNDS 
LIST OP AMERICAN PATENTS FOR BATING COMPOUNDS. 

Section I. Bating and Final Preparation for the Ooze ; 

Various synonymous terms used for Bating ; Use of the Bate ; the 
period in which the Hides remain in the Bating Solution . . .335 



.CONTENTS. XX 111 

PAGE 

Dung Bates ; Employment of Hydrochloric Acid for Dissolving Lime, 
as shown by MacBride in 1774 ; Carbonate of Ammonia employed by 
Warrington in 1841 ; Sugar used by Trumbull in 1847; Other sub- 
stances used ; Objections to the present method of Bating . . 336 

Bating as usually accomplished by placing the Hides or Skins in a Vat, 
with a circular tight bottom, over which vat is a revolving paddle- 
wheel ; the England wheels used for agitating the Bate Liquor illus- 
trated and described ; the Scouring Slicker . . . . .337 

Final Soaking before placing the Hides in the Ooze ; Lampert's Machine 
for Working Hides, with detailed description ..... 338 

Section II. Bating Compounds ; ZoUick offer's Process of Bating 
with Muriate of Ammonia, either alone or in combination with hen's, 
pigeon's, or dogs's dung ......... 341 

Another Process of Zollickoffer ........ 342 

Advantages claimed for this process ; Parkins's Bating Compound of 
Carbolic Acid, Muriate of Ammonia, and Alum .... 343 

Vickers and Holmes's Composition for Bating, consisting of a mixture of 
Sulphuric Acid with the Lime Liquor in which the Skins have been 
already treated for removing the Hair ...... 344 

Stack's Compound for Bating, consisting of Bran, Oil of Vitriol, and 
Salt 345 

McMurtrie's Bate of Glucose and Dried Sour Cheese ; Maynard's Bating 
Compound of a l^iquor composed of Water impregnated with Sulphur 
Dioxide, which has previously been employed in Soaking and Soften- 
ing Hides 346 

Advantages claimed for this Compound ...... 347 

Mullen's Process; Adamson's Process; Vast quantities of dilute phos- 
phoric acid formed in glue factories ; Siiderberg's Process . . 349 

AVilson's Process; Wells's Process ; Tucker's Process ; Swan's Process 350 

Turley's Process; List of all Patents for Compounds for Bating Hides 
and Skins issued by the Government of the United States of America, 
from 1790 to 1883 inclusive 351 



PAKT y. 

CHAPTER XVIir. 

HANDLING AND PLUMPING. 

Section I. Handling ; Old and New Methods of Handling . 352 
Connecting the Sides which are to be Handled with the Reel ; the Hand 
Reel; the Rocker Handler; England's Handling Apparatus with de- 
tailed description .......... 353 

England's Paddle Wheels for Handling ; the Vats in which these wheels 
revolve ; motion of the wheels ........ 355 



XXIV CONTENTS. 

PAGE 

Lenorth of time and speed at which to run these wheels ; Arrangement 
of the wheels ; Methods of Handling now obsolete in this country, but 
still used in Europe .......... 356 

Handling by placing the Stock in a large Revolving Drum ; Gorsiine's 
Handling Apparatus ; Steinmann's Apparatus for Handling Hides in 
the Lime-pits ........... 357 

List of all Patents for Tanners' Vats, Agitators, and Handling Appliances 
issued by the Government of the United States of America, from 1790 
to 1883 inclusive .......... 358 

Section IL Swelling ok Plumping 359 

Plumping by means of Sour Liquor; Botchford's Process for Distilling 

Sour Liquors ........... 360 

Plumping by means of Sulphuric Acid ; Introduction of this system by 
David MacBride, 1773 361 

CHAPTER XIX. 

LAYING AWAY. 

Leather not a Chemical Combination of the Animal Substance with the 
Tanning Substance ; Knapp's Experiments; Deductions to be drawn 
from these Experiments . . . . . . . . .364 

Lay-away Vats for Sole leather Hides ; Manner in which the Stock is 
laid away . . . . . . . . . . . 365 

The number of Layers, and period for each Layer . . . .366 

Practice for difi'erent kinds of Leather . . . . . . .367 

CHAPTER XX. 

SPLITTING LEATHER. 

The Cellar of an Upper-leather Tannery, with Arrangement of Machines, 
and the manner in which the Power is supplied ; View in the Tannery 
of Thomas E. Proctor, Peabody, Mass 368 

Splitting Machine invented by Alpha Richardson, 1831 ; Early inven- 
tion of Seth Boyden, Newark, N. J. ; Richardson's Union Splitting 
Machine ; Belt-knife Splitting Machine of Flanders and Marden ; 
Facilities afforded by these Machines . . . . . .369 

Practical Working of the Union Splitting Machine . . . .370 

A Modification of this Machine; Enos's Attachment to prevent injury 
to those working at the ordinary Splitting Machines, with detailed 
description . . . . . .. . . . .371 

McDonald and Begg's Leather Splitting Machine, with detailed de- 
scription . . . . . . . . . . . .375 

The Belt-knife Splitting Machine 3 78 

Cummings'sLnprovement in Belt-knife Splitting Machines, with detailed 
description ........... 380 

List of all Patents for Leather Splitting Machines issued by the Govern- 
ment of the United States of America, from 1790 to 1883 inclusive . 383 



CONTENTS. XXV 



PAET VI. 
CHAPTER XXI. 

SCOURING. 

PAGE 

The Tools used in the Hand Method of Scouring Leather . . . 385 

The Lockwood Automatic Leather Scouring and Setting Machine, with 
detailed description .......... 386 

Improvements in this Machine on that patented by the same Inventor in 

1876 391 

The Holmes's Scouring, Setting, and Hide Working Machine, with 

detailed description . . . . . . . . . .392 

Holmes's Improved Scouring Machine Parts . . . . .396 

The Fitzhenry Leather-dressing Machine ; Details of the latest Im- 
provements . . . . . . . . . . .398 

Burdon's Machine, with detailed description . . . . .401 

Daheney's Table for Leather Scouring Machines, with detailed descrip- 
tion 405 

List of all Patents for Scouring and Setting Machines issued by the Gov- 
ernment of the United States of America, from 1790 to 1883 inclusive 407 

CHAPTER XXII. 

STUFFING LEATHER — HAND STUFFING AND STUFFING WHEELS — STUF- 
FING AND CURRYING COMl'OUNDS — MACHINE FOR REMOVING GREASE 
FROM LEATHER — LIST OF AMERICAN PATENTS FOR STUFFING APPA- 
RATUSES AND FOR STUFFING AND CURRYING COMPOUNDS. 

Section I. Hand Stuffing and Stuffing Wheels . . . 408 
Stuffing Wheels ; First Stuffiing Wheel patented in this country invented 
by L. W. Fiske ; Peed and Winchester's Stuffing Wheel with de- 
tailed description .......... 409 

Carl's Stuffing Wheel, with detailed description . . . . .412 

List of Patents for all Apparatuses for Stuffing and Greasing Leather 
issued by the G"bvernment of the United States of America, from 1790 
to 1883 inclusive . . . . . . . . . . 414 

Section II. Stuffing Compounds ; Andrews's Compound . . 415 
Merrill's Compound . . . . . .. . . .416 

Williams's Compound, Glycerole of Egg . . . . . .417 

Thayer's Compound . . . . . . . . . .418 

'' B. S Oil" for Stuffing Compounds, Dewees and Green's Patent Process 

with B. S. Oil 419 

List of all Patents for Compounds for Stuffing Leather issued by the 

Government of the United States of America from 1790 to 1883 inclu- 



XXVI CONTENTS. 

PAGE 

sive. List of all Patents for Compounds for Currying Leather issued 
by the Government of the United States of America from 1790 to 
1883 inclusive 420 

Section IIL Machines for Removing Grease from Leather; 
Perkins's Machine for Removing Grease from Leather, with detailed 
description ........... 421 

List of all Patents for Machines for removing Grease from Leather issued 
by the Government of the United States of America from 1790 to 
1883 inclusive . 422 

CHAPTER XXIII. 

WHITENING LEATHER. 

French Pattern of Whitening Slicker; Beam now generally employed 
in Currying Shops; Common form of Curriers' Knives . .^ . 423 

Clements's Leather Whitening Machine, with detailed description . 424 

Smith's Leather Whitening and Buffing Machine, with detailed descrip- 
tion 428 

List of all Patents for Curriers' Slickers issued by the Government of the 
United States of America, from 1790 to 1883 inclusive. List of all 
Patents for Curriers' Knives, and for Machines for Sharpening Cur- 
riers' Knives, issued by the Government of the United States of America 
from 1790 to 1883 inclusive. List of all Patents for Machines for 
Whitening, Buffing, and Shaving Leather, issued by the Government 
of the United States of America, from 1790 to 1883 inclusive . . 430 

CHAPTER XXIV. 

BOARDING AND GRAINING BY MACHINERY. 

Advantages which have arisen from the introduction of Boarding and 
Graining Machines . . . . . . . . . .431 

Coogan's Boarding and Graining Machine, with detailed description . 432 
Hovey's Boarding and Graining Machine, with detailed description . 434 
Coogan's Machine for Boarding and Graining Morocco, as improved by 

G. W. Baker ^. , . 438 

JAst of all Patents for Machines for Boarding and Graining Leather, 
issued by the Government of the United States of America from 1790 
to 1883 inclusive .......... 439 

CHAPTER XXV. 

BLACKING LEATHER. 

Section I. Blacking and Smutting Appliances; The two forms 
of Blacking Brushes in common use ....... 440 

Bachelder's Leather Blacking, Coloring, and Dressing Machine, with 
detailed description . . . . . . . . . .441 



CONTENTS. XXVll 

PAGE 

Bryant's Machine for Smutting Leather, witli detailed description . 447 

List of all Patents for Apparatuses for Blacking Leather, issued by the 
Government of the United States of America, from 1790 to 1883 
inclusive ............ 449 

Section II. Blacking Compounds, Hayward's Flesh Blacking 449 
Shaw's Compound for Finishing Upper Leather ..... 450 
Putnam's Composition for Finishing Split Leather. List of all Patents 
for Blacking Compounds for Leather, issued by the Government of the 
United States of America, from 1790 to 1883 inclusive . . . 451 

CHAPTER XXVI. 

MACHINES FOR GLASSING OR POLISHING, PEBBLING, FINISHING, 
ROLLING LEATHER, ETC. 



. 454 

. 458 

. 460 

. 462 

. 463 

. 464 
ing, Finishing, Glass- 



Glass Slick 3r for Glassing by Hand ....... 453 

Martin's Machine, with detailed description . 

Friend's Machine, with detailed description . 

Hildreth's Machine, with detailed description 

Baker's Improved No. 4 Glazing Machine 

Baker's Ponj'-Glazing Machine 

Overhead Glazing .Machines ; Knox's Machine 

List of all Patents for ISIachines for Stoning, Polisl 

ing, Glazing, Flinting, Creasing, and Dicing Leather, issued by the 
Government of the United States of America, from 1790 to 1883 
inclusive ............ 465 

List of all Patents for Machines used for Pebbling Leather, issued by the 
Government of the United States of America, from 1790 to 1883 inclu- 
sive ; List of all Patents for Machines for Rolling Leather, issued by 
the Government of the United States of America, from 1790 to 1883 
inclusive ............ 467 

CHAPTER XXVII. 

MACHINES FOR MEASURING LEATHER. 

Leather Measuring Machines invented in the United States since 1877 ; 

Winter's Leather Measuring Machine ...... 468 

Williams, Moore, and Hurlburt's Leather Measuring Machine, Avith 

detailed description .......... 469 

Sawyer's Leather Measuring Machine, with detailed description . . 473 

List of all Patents for Machines for Measuring the Areas of Hides, Skins, 

and Leather, issued by the Government of the United States of 

America, from 1790 to 1883 inclusive 480 



XXVUl CONTENTS. 



PART Vll. 

CHAPTER XXVIII. 

SOLE LEATHER. 

PAGE 

Section I. General Remarks ; What is sought to be Combined in the 
Manufacture of Sole Leather ; Oak-tanned Sole Leather ; The Astrin- 
gent Principle of Oak and Hemlock Bai'ks 481 

" Hemlock Non-acid," and Hemlock Acid Leather; The Varieties into 
which Sole Leather is divided in this Country — Hemlock, Oak 
Slaughter, Oak Texas Hide, Union Slaughter ..... 4'82 

Process of making Oak Slaughter Sole Leather at Luraj', Virginia . 483 

Section H. Tanning and Finishing Oak Slaughter Sole 
Leather ........... 483 

Rolling Machine generally Employed for Rolling Sole Leatlier . . 485 

Section IH. Tanning Inside Sole Leather . . . . 486 

Section IV. Bleaching Hemlock Tan, and Union Tan 
Leather, Similar to Oak Tanning ; Process of E. W. Phillips 488 

Section V. Artificial Sole Leather; Pollock's Process for mak- 
ing Artificial Leather from Scraps and Waste . . . . .489 

Practical details of the process . . . . . . . .490 

Chemical Reaction which takes place in the process . . . .491 

CHAPTER XXIX. 

heavy upper leather — tanning and finishing the " side" and 
"split" — removing extractive matter from tanned leather 
— PROCESS for water-proofjng, dubbing, and whitening upper 
leather — improvement in tan presses. 

Section I. Tanning and Finishing the " Side" and " Split ;" 
AVhat are included under the head of Upper Leather ; the Hides and 
Skins from which Upper Leathers are produced .... 492 

Machinery now largely employed in the production of Leathers . . 493 

Whence Hides are generally imported into the United States ; Whence 
the supplies of Bark are obtained, and how purchased ; Preparation of 
the Hides ; Placing the Hides in the " Soaks ;" Splitting into Sides ; 
Placing in the Hide Mill ; Placing in clear cold Water . . . 494 

Removal of Hides to the "Limes;" Machine commonly employed in 
Salem, Mass., for unhairing ; the Drenching Wheels and Wash 
Wheels ; the Hide Worker ; Tanning ...... 495 

The Sides of Leather as hung over the poles in the Drying Yard, and 
showing a view of the Shops . . . . . . , . 496 



CONTENTS. XXIX 

PAGE 

Finishing the Sides . . . , . . . . '. .49 7 

The various Machines and processes used ...... 498 

Interior of the Finishing Room of an Upper Leather Manufactory, with 
the Pasting Tubs and Tables, Horses for receiving and moving the 
Leather, and the Bhicked and Pasted Sides suspended from Hooks in 
the Ceiling Racks; Finishing the Split; Head's Process for Soaking, 
Liming, Tanning, Blacking, and Gumming Hides intended for Upper 
Leather ............ 500 

Section II. Removing Extractive Matter from Tanned 
Leather; Plumer and Kernans's Process for Removing Extractive 
Matter from Tanned Leather ........ 503 

Section III. Processes for Water-proofing, Dubbing, and 
Whitening Upper Leather; Rady's Process for Water-proofing, 
Dubbing, and Whitening Upper Leather, and giving it a "Satin 
Finish" 504 

Treating Boots, Shoes, and Harness by tliis process ; Sponhouse's Method 
for Manufacturing Water-proof Leather ... . . . . 505 

Section IV. Improvements in Tan Presses ; Holmes's Tan Press; 507 
Daniels's Tan Press ; Weston's Tan Press, with detailed description 508 

CHAPTER XXX. 

GRAIN, SPLIT, AND BUFFED LEATHERS — TANNING AND FINISHING 
GRAIN, SPLIT, AND BUFFED LEATHERS — COMPOUNDS FOR PRODUCING 
IMITATION OF GRAIN AND MOROCCO LEATHERS. 

Section I. Tanning and Finishing Grain, Split, and Buff 
Leathers ; the above varieties of Leather produced in large quan- 
tities in this country ; the Bark and Hides used ; Details of the 
processes . . . . . . . . . . . .511 

Unhairing by Machinery . . . . . . . . .512 

Finishing Grain Leather . . . . . . . . .515 

Finishing Buff Leather . . . . . . . . .516 

CHAPTER XXXI. 

GERMAN HARNESS LEATHER VACHE LEATHER — MACHINE BELT 

LEATHER GREASED WITH TALLOW. 

The Hides used for these varieties; Handling the Hides . . .518 

Preparation of Vache Leather; Details of the process . . . 519 

Machine Belt Leather Greased with Tallow ...... 522 

Currying the Tallowed Leather ........ 523 



XXX CONTENTS. 

CHAPTER XXXII. 

MOROCCO LEATHERS. 

PAGE 

Section T. Tanning and Finishing Imitation of French 
Kid ; Brushed Kid ; Straight-grained Goat, Pebbled Goat, and Oil 
Goat ; What is understood by Morocco ; from what Skins Moroccos 
ai-e prod uced ; Commercial Classification of Morocco Leather in this 
Country ; Classification of Goat-skins employed in this Country for 
the Manufacture of Morocco Leather ...... 524 

Glove Calf and Glove Sheep ; Whence the Skins are obtained for the 
Manufacture in the United States ; Tanning Material usually em- 
ployed ; Preparing the Skins ; Lime Vats in a INiorocco Tannery . 5^5 

The Quantity of Skins treated at one time in large Morocco Tanneries ; 
Practical details .......... 52G 

Tanning ; Tan Tubs in a Morocco Factory ; Manner in v?hich the Skins 
are attached to the Spigots, and method by which the Skin Bags are 
filled with Sumach l^iquor ; Baker's Vat or Tank with Feeding Pipe, 
etc., with detailed description . . . . . . . .527 

Apparatuses of Dr. Turnbull, Patented 1844, and of Dudley and Brooks, 
Patented 1834 . 529 

Striking out and Drying ; the Drying Loft in a Morocco Factory, show- 
ing the Skins hung on Hooks on the Racks ..... 530 

Finishing Imitation French Kid ; Finishing Room in a Morocco Fac- 
tory 531 

Finishing Brushed Kid ; Finishing Straight-grained Goat ; Drying Loft in 
a Morocco Factory with the Skins spread out ..... 532 

The Finishing Room in which the Skins are Rolled and Glazed ; the 
Graining Board .......... 534 

Finishing Pebbled Grain Goat ; Finishing Oil Goat .... 535 

SkctionII. Tanning Apparatuses for Goat- and Shekp-Skins; 
Warner's Apparatus for Tanning Goat- and Sheep-skins, with de- 
tailed description .......... 530 

Walters's Filling Cup for Morocco Manufacturers, with detailed descrip- 
tion 539 

Hand Method of Tanning Morocco ....... 541 

Tanning Morocco in a Combined Wheel and Vat ; Halsej-'s Apparatus 
with detailed description . . . . . . . . .542 

Section III. Puttinc; Out Machines for Morocco; Vaughn's 
Machine for Putting Out Skins ; Hoffman's Putting Out Machine, with 
detailed description . . . . . . . . . . 545 

List of all Patents for Putting Out Machines and for Leather Fluffing and 
Grounding Machines issued by the Government of the United States 
of America from 1790 to 1883 inclusive ...... 550 



CONTENTS. XXXI 

PAGE 

List of all Patents for Machines for Evening or Making Leather of Uni- 
form Thickness issued by the Government of the United States of 
America from 1790 to 2 883 inclusive ...... 551 

Section IV. Compounds for Producing Lmitation of Grain 
OR Morocco Leather ; Smith's Compound ..... 551 

Process for Finishing Lower Grades of Leather similar to Morocco, the 
Invention of Tice and O'Connell ....... 552 

CHAPTER XXXIII. 

TANNING AND FINISHING SHEEP-SKINS. 

Section I. Tanning and Finishing Sheep-skin Fleshers for 
Linings, Bindeks, and Skivers; Importance of this branch of In- 
dustry ; the Sheep-skins used ........ 555 

Exterior of a Sheep-skin Tannery with the Slat Openings into the Dry- 
ino- Lofts for the Free Admission of Air ; Tanning Vats in a Sheep-skin 
Tannery ; Drying Lofts in a Sheep-skin Tannery .... 556 

Finishing Department of Sheep-skin Tannery, where the Skins are Rolled, 
Glassed, or Pebbled by Machines ; Dressing Sheep-skin Fleshers for 
Glove Bindings ; Hart's Process ....... -557 

Section II. Improved Methods for Dressing and Tawing 

Sheep-skins; Manassee's Method for Tawing Sheep-skins . . 558 

Hibbard's Process for Preparing and Tanning Sheep-skins . . . 559 

Hesthal's Process for Dressing Sheep-skins, etc. ..... 560 

Section III. Artificial Sheep-skins for Linings ; Evans's Imi- 
tation Sheep-skins .......... 561 

CHAPTER XXXIY. 

LACE LEATHER. 

Lace Leathers and their Mode of Preparation ... . 563 

Junior's Methods of Manufacturing Lace Leather . . . . 565 

Quick Tanning Process for Lace and Whip Leather by Bartenbach and 

Richter; Loescher's Method for Manufacturing Lace Leather . . 567 

Coupe's Stretching Machine, with detailed description .... 568 

Tidd's Softening Machine, with detailed description .... 570 

CHAPTER XXXT. 

HORSE LEATHER FOR FOOT-WEAR. 

Origin and History of this Industry ....... 572 

Details of the Process of Manufacture . . . . . • .573 



XXXU CONTENTS. 

CHAPTER XXXVL 

RUSSIA LEATHER — THE MATSfUEACTURE OP RUSSIA LEATHER 

RUSSIAN METHOD OF PREPARING AND APPLYING THE MORDANT AND 
DYE — MANUFACTURE OF BIRCH OIL — ARTIFICIAL RUSSIA LEATHER. 

PAGE 

Section I. The Manufacture of Russia Leather; Uses to 

which this Leather is applied .... .... 574 

Russia Leather at the Centennial Exhibition ; Pi-ocess of Manufacturing 

this Leather as conducted in the United States ..... 575 

Dyeing the Leather, Black or Red ; Mordant ..... 576 

Graining the Hides ; Towein's Graining Machine ..... 578 

Section II. Manufacture of Birch Oil ..... 578 

Processes for Distilling this Oil ; Fischerstroern's Method . . . 579 
Grouvelle and Duval-Duval's Process; Payen's Experiments; Distill- 
ing Apparatus ........ ... . 580 

Products obtained by the Distillation ....... 581 

Section III. Artificial Russia Leather; "Rubber Cloth," 
" Enamelled Cloth," and "Leatherette" ...... 581 

Freely's Method .......... 582 

CHAPTER XXX VII. 

ALLIGATOR LEATHER. 

Purposes for which this Leather is used ; the Alligator Skins . . 582 

Tanning and Finishing the Skins ........ 583 

CHAPTER XXXYIIL 

PATENT, JAPANNED, OR ENAMELLED LEATHER. 

The Hides for this Leather and whence obtained ; the Material cm- 
ployed for Tanning .......... 585 

Details of the Operation ; the Bate Stone ; the Vats with Revolving 
Wheels 586 

Stretching ; Oliver and Howell's Frame for Stretching Leather, with 
detailed description .......... 588 

Compounds for Finishing Japanned or Enamelled Leather ; their Com- 
position and Application ......... 590 

Pumicing ............ 591 

Varnishing and Drying; Merrill's Process for Boarding the Leather; 
Hoey's Process for renewing the surface of Japanned Leather; Pre- 
paring the cut surface of Split Leather for manufacturing Japanned or 
Enamelled Leather 592 



•CONTENTS. XXXin 



Patterson's Method for forming an Artificial Grain on the Hide after it 
has been buffed or split ......... 59.'! 

Japanned Leather in imitation of Alligator Skin, Merritt's Process . .594 

Substitute for Patent Leather ; List of all Patents for Methods for manu- 
facturing Enamelled, Japanned, and Patent Leathers, issued by the 
Government of the United States of America from 1790 to 1883 inclu- 
sive ........'.... 595 

List of all Patents for Apparatus for Stretching Jjeather issued by the 
Government of the LTnited States of America, from 1790 to 1883 
inclusive ............ 596 



PART VIII. 
CHAPTER XXXIX. 

TANNING PROCESSES. 

Large number of Processes invented for facilitating the Tanning of 
Leather ; but few of value ; Precautions to be taken in adopting new- 
Processes ; Most of the Leather Tanned in the United States Tanned 
by one of three methods . . . . . . . . .597 

Tanning Processes : Snyder's; German's; L-ving's; Hibbard's . . 598 

Fulton's; Enos's ; Keeler's ; Wattles' s ; Gould's .... 599 

Hatchs's; Daniels's; Kennedy's ....... 600 

Noble's • 601 ' 

Garge's; Page's . . . . . . . . . " . . 602 

Robinson's ............ 603 

Wyeth's 604 

Pickard's ; Wheelock's ......... 605 

Kidder's; Jenkins's . . . . . . . . . 600 

Ruemelin's Tan Vat, with detailed description ..... 607 

List of all Patents for Processes for Tanning Leather, issued by the Gov- 
ernment of the United States of America, from 1790 to 1883 in- 
clusive 609 

List of all Patents for Processes, Employing Apparatus for Tannino- 
Leather, issued by the (xovernment of the L) nited States of America, 

from 1790 to 1883 inclusive 614 

I^ist of all Compounds and Materials for Tanning and also for Tawing 
Leather, and for Preparing Raw Hides, that are especially claimed or 
mentioned in any Patent issued by the Government of the United 
States of America, from 1790 to 1883 inclusive .. .. .. .616 

C 



XX XIV CONTENTS. 



CHAPTER XL. 

TANNING AND CURRYING HIDES AND SKINS WITH THE HAIR AND 

PUR ON. 

PAGE 

Pingree's Processes ; Johnson's Process ...... 620 

Coe's Process ; Cai-ter and Keith's Process ...... 621 

Tanning and Coloring Beaver, Otter, and any other Skins with the Fur 

or Hair on ; Bugh's Method . .622 

The Preparation of the Tan Liquor ....... 628 

To Color Furs ; Method and Machine for Dyeing the Wool on Sheep- 
skins ; Jack's Apparatus for Dyeing the AVool on Sheep-skins, with , 

detailed description .......... 624 

CHAPTER XLI. 

MINERAL TANNING. 

What is understood by Mineral Tanning; Attempts to Substitute Mineral 
Substances for Vegetable Tannin made more than a hundred years 
ago; Ashton's Patent for Tanning with Ferric Salts, 1794 . . 626 

Bordier's Patent for Converting Hides into Leather by means of Mineral 
and Earthy Substances, especially Ferric Sulphate, 1842; Molac and 
Triedel's Patent, 1855 627 

Knapp's Patent, 1861; Pfanhauser's Patent, 1864; Process of Cavalin, 
the first use of bichromates . . . . . . . .628 

All of the foregoing processes abandoned ; Fresh Impetus given to the 
subject of Mineral Tanning by Knapp in 187 7 ; Knapp's Process of 
Tanning Avith Ferric Salts, with detailed description . . . 629 

Heinzerling's Method of Tanning with Chromates, etc. ; Heinzerling's 
Patents obtained in the United States in 1880 and 1881 ; Detailed 
description of Heinzerling's Process ....... 633 

Comparative Experiments of Dr. J. Clark, of Glasgow, as to the Solu- 
bility of the Tannin in Chrome and other Leathers .... 636 

Quantity of Potassium Bichromate withdrawn from different kinds of 
Leather Tanned by Heinzerling's Process, and treated in different 
modes ; Tannin withdrawn from English Tanned Leather by similar 
modes of treatment . . . . . . . . . .637 

Conclusions of Dr. Clark ; Tables giving the results arrived at, at two 
English Experimental Stations as to the Stretching Capacity of 
Chrome and Tan Leathers ........ 688 

Aluminium Tanning ; Method of Dr. Putz, of Passau ; List of all Patents 
for Employing Mineral Substances for Tawing Hides and Skins, issued 
by the Government of the United States of America, from 1790 to 
1883 inclusive 641 



CONTENTS. XXXV 



CHAPTER XLII. 

TAWING — FRENCH OR ERLANGER METHOD OF TAWING — DANISH GLOVE 
LEATHER — JENNINGS'S METHOD OF TAWING — DEFECTS OF ALU MED 
VARIETIES OF LEATHER — MANUFACTURE OF OIL OR CHAMOIS 
LEATHER — PRELLER'S METHOD OP TAWING — KLEMM'S OIL LEATHER. 

PAGE 

French or Erlanger Method of Tawing ; this method employed in the 
Manufacture of Soft Leather for Gloves, originally a French Industry 
brought to a high degree of perfection in Germany and Austria ; 
Qualities demanded in such Leather ....... 642 

Buying and Preserving the Raw Skins . . . . ... . 643 

Damage by Moths .......... 645 

Best means of getting rid of Moths ....... 646 

Manner of working the Skins ; Dilference between the Ordinary and the 
French Methods ; Work of Tawing according to the French or Er- 
langer Method ; How Divided : 1. Soaking and Rinsing . . . 647 

2. Liming and Depilating ......... 648 

3. Treatment in Bate of Dog Excrements . . . . . . 649 

Washing Wheel for Fulling used in Germany and France ; Preparing the 

Bate 650 

The manner of using the Drum for Fulling Machine . . . . 651 

Treatment of the Skins after the removal from the Bate or Fulling 

Drum; 4. Branning . . . . . . . . . 652 

Precautions to be observed ; 5. Tawing ; the Object of this Operation ; 

Various Tawing Pastes ......... 653 

The Object of using a Tawing Paste, such as plays a prominent part in 

the Manufacture of French Glove Leather . . . . .657 

Experiments of Knapp in regard to Tanning and Tawing . . . 660 

6. Finishing; Polishing with a Polishing Steel or Agate Roller . . 661 

Polishing Roller kept Hot by a simple device . . . . .662 

The use of Flat Irons instead of Polishing Rollers ; Glazing of inferior 

qualities of Leather before Smoothing . . . . . .663 

Glazed or Glac6 Leather ; Aikins's Method of working Lamb-skins into 

Glove Leather ........... 664 

Watts's Method of working the Skins of Lambs, Goats, and Dogs into 

Glove Leather 666 

Main's Process of Finishing Alumed Leather ..... 667 

Danish Glove Leather .......... 668 

Jennings's Method of Tawing . . . . . . . .669 

The Theory of this Method . .672 

The object of adding Zinc Filings or a soluble Zinc Salt to obtain a 

higher degree of Whiteness ; Tawing by Jennings's Method more 

constant than by the ordinary process, and the Leather resists the 

action of Water better ; the cause of this ; defects of Alumed varie- 



XXXVl CONTENTS. 

PAGE 

ties of Leather ; either natural ones or result from Storing or the man- 
ner of Working . . . . . . . . . .673 

Injury to which Skins are liable in Branning . . . . .675 

How to prevent this evil ; defect technically called " Shading" . . 676 

])efect of what is called Rotten or Burned Leather ; investigations on 
this subject, and remedy proposed by Prof. Knapp . . . .677 

Manufacture of Oil or Chamois Leather ...... 679 

The Heads under which the Operations in making this Leather may be 
divided ; Depilation and Frizzing ....... 680 

First Jiming ; Stretching and Scraping, upon the Flesh Side, and 
partly upon the Grain Side ; Second Liming ; Branning . . . 6§1 

Fulling in the Oil ; the Oil to be used . 682 

Fulling the most important and delicate Operation in Oil Tawing ; Test 
of the Skins being sufficiently Oiled . . . . . . . 683 

Heating the Skins ; Finishing and Dressing ...... 68.5 

Stretching L-on . .687 

Bleaching and Pumicing Chamois Leather for Gloves ; to obtain the 
Shade of Buff Leather for Pantaloons, Gloves, etc. ; to clean dirty 

Leather 688 

Twisted Leather; Preller's Method of Tawing; the Animal and Vege- 
table substances and the Salt used . . . . . . . 689 

The Composition of the Mixture ; Treatment of the Skins . . . 690 

Drying; the Leather prepared according to Preller's Method called " H 
B Crown;" the weight of Leather Tanned by Preller's Process 
yielded by 220 pounds of Green Hide ; Superior strength of Preller's 
Leather . . . . . . . . . . . .691 

Purposes for which Crown Leather is adapted ; Time required for mak- 
ing Leather by Preller's Process ; Capacity of Crown I^eather to re- 
sist Water ; Behavior of Crown Leather Boiled in Water ; Softness 
of Crown Leather .......... 692 

The Theory of Pi-eller's Process; Preparation of Klemm's Oil Leather; 
Manner of preparing the Hides ; Tanning ..... 693 

Subsequent Treatment; advantages of this Process; Prof. Reusch's Ex- 
periments in regard to the strength of this Jjcather ; Coloring, Greas- 
ing, and Finishing ; this process corresponds in many points with 
Preller's, and does not differ materially from the more rational methods 
of the manufacture of Glac6 Leather ...... 694 

Prof. Fehling's Experiment with Klemm's Leather ; Dr. F. Knapp's 
Process of Tanning with Salt Solutions and Soap Baths ; Details of 
this process ........... 695 

Character of the Leather obtained ; the nature of the process ; Advan- 
tages upon the score of economy ....... 696 

White Glazed Leather of great Softness and Suppleness obtained by 
Knapp by Macerating thorouglily cleansed Skins of Lambs and Goats 
in Saturated solution of Stearine in Spirit of Wine .... 697 



CONTENTS. XXXVll 



PAET IX. 
CHAPTER XLIII. 

DYEING LEATHER. 

PAGE 

Section I. General Remarks; Light the source of all Color; the 

"Spectrum" ........... 698 

The Primitive Colors (J99 

The importance of the Art of Dyeing ; Chemistry and its relation to 
Dyeing ; in composing shades, only in fact, the three Primary Colors are 
at disposal — Red, Yellow, and Blue ; the limitless combinations into 
which these Coloi's can enter ; the part which Water plays in these 
modifications and combinations ; Water for the Dyer what the White 
Color is for the painter ; Modifications of Color caused by the use of 
Water 700 

A "graduated line of color, " and a "modified color;" Examination 
and Dissection of a Spectrum showing twelve colors in it ; producing 
these twelve colors Avith Red, Yellow, and Blue .... 7^1 

'JMie measure for a Leather Dyer is what Scales and Weights are to the 
Chemist ; the effects of mixing certain proportions of Dye Stuffs of 
different colors . . . . . . . . . . . 702 

An illustration of the transition of colors through their countless modifi- 
cations by a so-called Color-ball ; the circle of normal colors ; the 
" category" of a color ; the category not identical with shades . . 703 

Shades 704 

Section II. Mordants; Acids ....... 705 

Mineral Acids; Sulphuric Acid ........ 706 

Nitric Acid ; Hydrochloric Acid . . . . . . . .707 

Organic Acids ; Acetic Acid ; Oxalic Acid ...... 708 

Citri(> Acid and Tartaric Acid ; Bases ; Potassium Hydrate and Sodium 

Hydrate 709 

Ammonia ; Lime . . . . . . . . . .710 

Salts; Sulphates; Ferrous Sulphate or Green Vitriol . . . .711 

Cupric Sulphate or Blue Vitriol ; White Vitriol or Zinc Sulphate ; 
Aluminium Sulphate ;* Alum . . . . . . . .712 

Chromium Alum . . . . . . . . . . .713 

Nitrates ; Ferric Nitrate ; Lead Nitrate ; Chlorides ; Sal Ammoniac ; 
Ferric Chloride ; Stannous Chloride or Tin Salt ; Stannic Chloride- 
Tin Composition or Physic ........ 714 

Common Salt or Sodium Chloride ; Acetates ; Ferric Acetate ; Alumi- 
nium Acetate . . . . . . . . . . .715 

Plumbic Acetate ; Cupric Acetate or Verdigris . . . . .716 



XXXVIU COiSTTENTS. 

PAGE 

Tartrates ; Potassium liitartrate or Crude Tartar ; Carbonates ; Potas- 
sium Carbonate or Potash . . . . . . . .717 

Sodium Cai'bonate; Potassium Bichromate ; Lead Chromate . "718 

Yellow Prussiate of Potash or Potassium Ferrocyanide ; Red Prussiate 
of Potash or Potassium Ferriccyanide . . . . . .719 

Soaps ............. 720 

Section III. Mechanical Work of Dyeing Alumed Leather 
AND Directions eor Preparing and Applying Various Vege- 
table Dyes; Dyeing the Skins upon the Flesh Side . . . 721 
Dyeing the Skins upon the Grain Side ; Dyeing by Dipping . . 723 
Dyeing by Painting ; by the Grenoble Method ..... ?24 

The English Method 725 

French Method 726 

Light-Leather Brown . . . . . . . . . .729 

Olive; Mi-fonce Brown; Bottle Green; Method of Brushing the Dye 
Liquor on the Skins ......... 730 

French Knee Contrivance for "Boarding" or Softening and Overletting 

the Skins . . . . . . . . . . .732 

% 
Section IV. Receipts for Various Vegetable Colors, and 

FOR Coloring Leather WITH Mineral Pigments . . . 732 

Dark Brown ; Light Brown ; Olive Brown ; Catechu Brown ; Catechu 
Gray-Brown ; Coffee Brown ; Dark Green ; Olive Green ; Light Olive- 
Green ; Picric Green ; Lemon Color ...... 733 

Quercitron Yellow ; Barberry Yellow ; Rust Yellow ; Orange ; Violet ; 
Mixed Brown ; Sap Green ; Nankin Yellow ; Dai'kBlue; Red . 734 

A-lazarine Red ; Scarlet ; Red ; Dark Gray ; Iron Gray ; Black ; Min- 
eral Pigments . . . . . . . . . . . 735 

Sky Blue ; Brown ; Chrome Yellow . . . . . . . 736 

Section V. Dyeing Chamois or Oil Leather .... 736 

Madder Red; Preparing the Skins ; Mordanting; the Madder Bath . 737 
Giving the Dyed Skins more Lustre ; Blue in all Shades by Dyeing in 

the Indigo Vat ; Green ......... 738 

Yellow; Brown; Black 739 

Section VI. Dyeing with Aniline Colors and the Methods 
OF their Preparation ; Aniline Color especially suitable for Color- 
ing I^eather . . . . . . . ■ . . . . 740 

Oil or Chamois Leather Dyed in the same manner as Alumed Leather 
with Aniline Colors ; Aniline Colors for Parchment Dyeing ; Aniline 
Violet; Perkins's Violet ; Parisian Violet ; Hofmann's Violet ; Rosa- 
niline Violet ........... 741 

Dahlia; Aniline Blue; Bleu de Paris; Bleu de Lyon; Ordinary Ani- 
line Blue ; Aniline Green ; Aldehyd Green ..... 742 



CONTENTS. 



XXXIX 



Ethyl Rosaniline Green ; Emeraldine ; Aniline Yellow ; Ordinary Ani 

line Yellow; Zinaline ; Chrysaniline ; Aniline Red . 
Aniline Brown ; Havana Brown ; Bismarck Brown ; Aniline Black 
Lucas Aniline Black . . . . 

Coralline ; Azuline .......... 

Phenol Brown ; Naphthalene Colors ; Dinitro-Naphthalene 

Section VII. Dyeing SuxMach-tanned Skivers with Aniline 
CoLOKS ; Samples of Leather Dyed by some of the following ReceijJts 
No. I. Methylene Blue O, Patented 

No. II. Azobenzole Fast Crimson RR, Patented; No. III. Naphthol 
Yellow L, Patented ; No. IV. Leather Brown .... 

No. V. Victoria Green; No. VL Dark Rose Pink B ; No. VII 
Orceine B .......... 

No. VIII. Orange BR ; No. IX. Bismarck Brown R . 

No.X. Fast Brown; No. XI. Soluble Blue R ; No. XII. Fast Red 
R, Patented 

No. XIII. Brilliant Green ; No. XIV. Russia Green ; XV. Rose 
Bengal ........... 

No. XVI. Scarlet, No. 2; No. XVII. Nankeen Brown; No. XVIII 
Dark Nankeen Brown ........ 

Section VIII. Dyeing Russia and Morocco Leathers with 
Aniline Colors ; Eitner's Directions for the Use of Aniline Colors, 
prepared by the Aniline Manufacturing Company, of Berlin 

Russia Leather Red G Light ; Russia Leather Red GR medium ; Russia 
Leather Red R Dark ; Dyeing Skins ; Producing the Odor of Russia 
Leather ; Production of Yellow and Yellowish-brown Shades . 

Dyeing Leather Golden Orange ; Production of the Reddish Shade of 
this Group of Colors ; A Pure Orange ; A Half Dark-pale Blue, so- 
called Marine Blue ; Pale Blue with a Pure Blue Shade; Dark Blue ; 
A Beautiful Bright Green ........ 

Violet Color; Convenience of using Aniline Colors; Martin's Yellow 
for Pure Yellow. Tones ; Orange Tones of the Redder Shade; The 
Intermediate Shades from Pure Yellow to the Reddest Orange; How 
the Dyeing is accomplished ........ 

Impai'ting a Lustre to Harness Leather; To give Leather Sti-aps at the 
same time a Color and a Lustre with Orange Fat Color 



74o 
744 
745 
746 
747 



748 

749 

750 
751 

752 



754 



754 



755 



•56 



(57 
r58 



CHAPTER XLIY. 

COMPOUNDS FOR COLORING AND POLISHING LEATHER. 

A Black consisting of an Ammoniacal Solution of Shellac, and the 
Aniline Color knoAvn as " Pourrier's D Blue Aniline" . . . 758 

Protochloride of Iron in Solution as a Basis for Black for Skins ; Pre- 
paring Raw Hides and imparting Black, Maroon, and Purple Colors . 759 



xl CONTENTS, 

PAGE 

An Intense Black, etc., prepared from Aniline Colors, mixed with 
Alcohol, etc ■ 761 

Black Staining Compound for concealing defects in Leather and for 
applying to Pocket-books, composed of Aniline Colors, Naphthaline, 
etc 762 

Compound for imparting a lustrous Black Gloss to Leather ; Dyeing 
Leather, containing Tannic or Gallic Acid, Black, by subjecting it to 
the action of a Vanadic Compound ....... 764 

Gilding and Ornamenting Leather for Suspender Ends, etc. ; Gilding 
Leather ; Bronze Dressing for Leather . . . . . .76.5 

Aniline Bronze Colors of Various Shades applicable to Jjeather . . 7<66 

Producing upon Leather Various Shades of Light Brown and Darker 
Colors by the Combination of Oxalic Acid, Salt of Tin, and Potash, 
with Nut-gall and Sulphate of L'on . . . . . . .767 

Coloring Leather with Aniline upon a Starch Surface and jjroducing an 
appearance similar to Marbled Paper ...... 768 

Forming a Solution for Staining Tawed Leather, consisting in mixing 
Clay, Water, Common Salt, Sulphuric Acid, Brewer's Yeast, Alum, 
Hemlock Extract, and Terra- Japonica . . . . . .769 

Preparing, Coloi-ing, and Polishing Light Skins for Car Seats, Trunk 
Covers, etc. . . . . . . . • . . .770 

Composition of Glycerine, Resinous and other Substances atfording a Base 
for imparting a High Polish to Jjeather ; Composition for Polishing, 
Water-proofing, and Coloring Leather . . . . . .771 

Polish for Leather used for Bags, Satchels, etc. . . . . .772 

Coloring partly Tanned Hides and Skins by the employment of a Bath 
of Tin, Acid and Water, and Turmeric ; Compound for Changing the 
Color of Leather, especially the Color of the Soles of Boots and Shoes 773 

Compound for Whitening Leather . . . . . . .774 

List of all Patents for Compounds for Polishing and Coloring Leather, 
issued by the Government of the United States of America, from 1790 
to 1883 inclusive .775 

Index . . . . . . . . . . . . .777 



THE 



MANUFACTURE OF LEATHER. 



PART I. 



CHAPTEE I. 

HIDES AND SKINS — THE VARIETIES OF HIDES AND SKINS USED FOR 
LEATHER — REMOVING- HIDES AND SKINS FROM ANIMALS — 
SELECTING HIDES AND SKINS — FRAUDULENTLY INCREASING 
THE WEIGHT OF HIDES — PRESERVING- HIDES — LIST OF AMERI- 
CAN PATENTS FOR PRESERVING HIDES — COMMERCIAL CLASSI- 
FICATION OF HIDES. 

From a very early period the hides and skins of animals have 
been doubtless much employed to contribute, first, to the neces- 
sities, next to the comforts, and finally, to the luxuries of man, 
being easily obtainable and adapted for shelter, apparel, and for 
a large number of articles of general utility. 

The origin of their use is more likely to be traced to moun- 
tainous than to low and warm districts, as in the first the animal 
food was desirable, and warmer clothing more necessary than 
in the latter, where man originally lived, between the tropics, 
under wide-spreading and protecting palm-trees, where food 
came spontaneously from the earth, and clothing was neither 
used nor requisite, and was not employed until circumstances 
finally compelled him to gradually migrate towards the poles. 

Then, as necessity has always been the mother of invention, 
mankind acquired sufficient knowledge to select the tender por- 
tions of plants and form them into clothing, and when they 
3 



34 THE MANUFACTUEE OF LEATHER. 

reached greater altitudes and colder districts to slaughter ani- 
mals, using the flesh for food, and the hides for shelter or cloth- 
ing, and, appreciating the use of plants, agriculture was prac- 
tised, and for the same reason animals were valued and the 
breeding of them received much attention. 

This branch of industry was carefully cultivated ; but, accord- 
ing to the economy of nature, mammiferous animals, as a class, 
seem destined from earliest times to have preserved a constant 
equilibrium in the number of animated beings that at all periods 
have held their existence on the surface of the earth. 

The quarrel between Laban and Jacob, in 1739 B. C, gives 
us an insight into the manner of conducting the cattle business, 
and the class of animals that were considered profitable. 

The same disposition to make contracts and then to seek to 
break them was just as common then as now. Laban, for a 
consideration of service, sold to Jacob a certain interest in the 
sheep and other animals, and then, when he saw that the pur- 
chaser was getting the best of the agreement, he changed 'it, 
and again he found that he was the sufferer. Jacob was the 
shrewdest cattle-trader of history, and was more forbearing 
than is the custom now, as he allowed Laban to change his inte- 
rest ten times in their dealings before he took his part of the 
cattle, camels, asses, and other chattels, and departed secretly 
from the Syrian, turning his back on the East, and his face 
towards Beersheba, which he had left about twenty-one years 
previously. 

In 1918 B'. C, when Abraham and Lot went up out of Egypt 
into the south, we are told in the thirteenth chapter of Genesis 
that they were both rich in cattle, in silver, and in gold. After 
reaching Bethel, because the land was not large enough to con- 
tain their vast herds, and also on account of the strife between 
the herdsmen of their separate cattle, the same as the "cow- 
boys" of our plains to-day, they divided. Lot journeyed east- 
ward, and chose the watered and rich plains of Jordan, and 
pitched his tents near Sodom. 

Nothing seemingly pleases the herdsmen or " cow-boys" of 
the present time so much as to be convenient to a wicked city, 
and doubtless those in Lot's employ were gi'eatly elated at being 



HIDES AND SKINS. 35 

SO near to Sodom and Gomorrah. Human nature has been the 
same in all ages; the wicked delight to dwell in iniquity; it is 
their life, their happiness. 

After the departure of Lot the plain of Marare was selected 
by Abraham, and the land further than he could see in all 
directions was his. 

In our own day we have great ranches, containing enormous 
herds of cattle, distributed through Texas, Colorado, New 
Mexico, Southern California, and other portions of the coun- 
try; but for extent of territory and number of animals it is not 
probable that there are any to compare with the possessions of 
either Abraham or Lot. 

From the omission of the census to include the business of 
the retail slaughtering establishments in its statistics, and from 
the manner in which the exports of cattle are recorded at the 
ports of exit, it is not possible to form an accurate estimate and 
classificatioli of the annual production in this country; but as 
cattle-breeding is one of our principal industries, it is important 
to that interest, as well as to that of tanning, that some such 
record and classification should be made. 

In accordance with the universal assent of mankind, the em- 
pire of nature has been divided into three kingdoms : — 

1. Mineral. 

2. Yegetable. 

3. Animal. 

With each of these we shall have more or less to do; of the 
first in the preparation and use of mineral tannins, the second 
of vegetable tannins, and of the third the hides and skins of 
the mammalia order of animals. 

The mineral kingdom comprises all substances which are 
without those organs necessary to locomotion, and the due per- 
formance of the functions of life. They are composed of the 
accidental aggregation of particles, which, under certain circum- 
stances, take a constant and regular figure, but which are more 
frequently found without any definite conformation. The vege- 
table kingdom covers and beautifies the earth with an endless 
variety of form and color. It consists of bodies organized, but 
destitute of the power of locomotion. They are nourished by 



36 THE MANUFACTUEE OF LEATHER, 

means of roots; they breathe bj means of leaves; and propagate 
by means of seed, dispensed within certain limits. The animal 
kingdom consists of sentient beings, that enliven the external 
parts of the earth. They possess the power of voluntary mo- 
tion, respire air, and are forced into action by the cravings of 
hunger or the parching of thirst, by the instincts of animal pas- 
sion or by pain. 

The skins of the most important of the mammalia class of 
animals, and the alligator of the fish family, are all with which 
we shall have to do of the six classes into which Linnaeus li<as 
divided the animal kingdom. The bodies of nearly the Avhole 
species of animals belonging to the mammalia class are covered 
with hair bestowed in proportion to the necessities of the animal 
and the nature of the climate which it inhabits, and it is chiefly 
with the removal of this hair and the preparation, or rather the 
conversion, of the skin into leather that it shall be the object 
of this book to deal. 

There is no way in which to ascertain at what period the art 
of removing the hair and wool and manufacturing a fabric from 
them was acquired ; but the art was not unknown in the valley 
of the Tigris and Euphrates before the date to which any. of 
our histories reach, and Goguet plausibly conjectures that the 
earliest fabrics were felted, not woven. But the distaff and the 
loom before a great while again revolutionized the manufacture, 
and we are told that Abraham, in 1913 B. C, five years after 
parting from Lot, as has been previously mentioned, refused to 
take anything from the King of Sodom, "from a thread even to 
a shoe latchet." 

It was centuries, however, before the inventions perfected on 
the plains spread towards and finally reached the scattered tribes 
of the colder places, and still longer before the sheep with 
straight hair, bred on the plains of Africa or Mesopotamia, 
could be acclimated to those colder countries, in which the 
straight hair was converted into the matted, curly wool which 
we find to-day on these animals. 

During all this time, among these remote tribes, the skins of 
animals continued to form the dresses or apparel of the people, 
and necessity taught the method of preparing them in some 



HIDES AND SKINS. 37 

manner, and thus the use of skins beyond the limits of higher 
civilization continued to he general. 

Herodotus tells us that the tribes of the Caspian Sea used seal 
skins for clothing, Strabo speaks of the Massagette wearing fur 
dresses, and both Ctesar and Lactantius mention the reindeer 
clothing of the German tribes ; and, in fact, so general was their 
use among the less civilized tribes, that the classical authors 
used the term "skin dressed" as descriptive of the savage. 

The barbarians clung to this style of dress, which added to 
their savage expression of features, and made them terrible to 
behold. The British Museum contains a marble bust of one of 
these characters found in Trajan's Forum, Eome, the expression 
upon the face of which is that of the most repulsive and savage 
character, and which has probably increased to a much greater 
degree by these strange garments. 

The nature of the preparation with which the skins were 
treated, in order to secure their preservation, we have no accu- 
rate way of ascertaining; but they were subjected to some pro- 
cesses of treatment, in order to prevent their putrefaction. 

Goguet has surmised as to the manner of the origin of the 
art of tanning, and he has made some very ingenious conjec- 
tures as to its discovery, based on the method used by the- 
North American Indians, Greenlanders, and Icelanders in. the 
preparation of ^ skins. 

Among all these people and tribes, depilation by maceration 
in water is common, and it may have been suggested, as Fost- 
rooke has stated, by the natural process of depilation or removal 
of the hair, as in the cases of drowned animals,' when macera- 
tion is plainly observed. 

Advancing civilization gradually superseded the use of hides 
and skins for the construction of boats and tents, and their use 
for clothing and other purposes, in a greater portion of the 
world. Still so great is the continuously increasing employment 
for the products of hides and skins, that many of the chief 
industries of the world are supported from these useful and 
bountiful supplies of nature. 

When these materials are intelligently cared for and treated, 
they become wealth by contributing to the necessities, comforts. 



38 THE MANUFACTURE OF LEATHER. 

and luxuries of man, who cannot create; but only take that 
which God has placed at his disposal, and by the labor of the 
body, or an effort of the mind, impart to it a value, and make 
it exchangeable, either into money, or convertible into other 
things which he desires. 

If the buffalo or other valuable animal be slaughtered on our 
own plains, those of South America, or any other portion of the 
globe, and the hide or other marketable portion be not removed 
and preserved, then it is simple waste, but this is one of the 
conditions inseparable from the absence of man, from whom .all 
value comes, and of diversified industries, which admit of a 
growth of the power of association, and a utilization of what 
have before been regarded as waste products. 

Then again, if the hides or skins of such animals be not prop- 
erly cured or treated, so as to arrive at the place of marketing 
in a perfect condition, it is again waste, and the punishment for 
such lack of intelligence is visited upon the vender by the pur- 
chaser in the shape of loss or deduction from the price. 

So through each step in the production of leather, from the 
moment of the slaughtering of the animal, until the finished 
product reaches the final purchaser, it is the duty of owners, 
managers, and employes in every branch to preserve the value, 
and economize at every point, both in the use of best processes 
and machinery, and in utilizing the offal, for in these days of 
close competition there is no room in the tanning or currying 
industries for extravagance. 

VARIETIES OF HIDES AND SKINS USED FOR LEATHER. 

The varieties of tanned leather are classed as hides, kips, and 
skins. 

The parts of hides are called butts, backs, flanks, etc., and 
form grades of thickness and quality. 

Hides are the skins of the larger animals, such as those of 
oxen, cows, and horses. 

Kirs exceed the size of calf-skins, and are the skins of small 
or yearling cattle. The East Indian kips are exported both 



HIDES AND SKINS. 39 

raw and tanned, from Calcutta and Madras, in such large quan- 
tities as to form a distinct branch of the leather trade. 

Skins are those of calves, sheep, goats, deer, pigs, seals, and 
various other kinds of fur-bearing animals, which latter, of 
course, usually preserve their hair. 

To man, mammiferous animals are immediately useful in 
various ways. The bodies of some afford him food, the skin 
shoes, and the fleece clothes. Some of them unite with him in 
participating in the dangers of combat with an enemy, and 
others assist him in the chase, in exterminating wilder sorts, or 
banishing them from the haunts of civilization. Many, indeed, 
are injurious to him; but most of them, in some shape or other, 
he turns to his service. 

Of these there is none more subservient to his purpose than 
the common ox, of which there is scarcely a part that he has 
not been able to convert into some useful purpose. Of the horns 
he makes drinking vessels, knife-handles, combs, and boxes ; 
and when they are softened by means of boiling water, he fash- 
ions them into a variety of other things. 

Glue is made of the cartilages, gristles, and the finer pieces 
of the parings and cuttings of the hides. 

Their bone is a cheap substitute for ivory, and is employed 
for the production of bone-black for clarifying sugars, and a 
carbonaceous substance employed in the manufacture of Prus- 
sian blue, also for the production of ammonia, and for fertilizing. 

The hair is used in various valuable manufactures; the suet, 
fat, and tallow are moulded into candles, or used for a variety 
of other purposes ; the tallow for instance is largely used in con- 
nection with fish oil for "stufl&ng" tanned upper-leather, and 
there are but few steam-engines on land or sea for which tal- 
low is not used as a lubricant in the cylinders, and in addition 
it proves a valuable item in the American export trade. 

Thus is every part of this animal valuable to man, who has 
spared no pains to bring it to the highest state of perfection. 

In proportion to the advancement in improving the breed of 
cattle, which is now so much practised in Europe and this coun- 
try, do the hides become less thick and degenerate into thin and 
spready pelts. 



40 THE MANUFACTUEE OF LEATHER. 

So generally has this improvement been practised in many 
portions of Great Britain, that the English tanners now make 
but little effort to obtain butt hides from their home cattle, and 
look mostly to South. America, Spain, and Portugal for the 
slaughtered butt hides which they use. 

The unimproved original stock on our plains will probably sup- 
ply us with thick hides for a long period yet to come, and with 
Mexico so conveniently connected with us by railroads, there is 
no immediate danger of our suffering for the want of butt hides 
from the improvement of our breeds of cattle. 

Cattle-skins form the chief source of supply for tanneries, 
and it is not necessary here to enumerate the purposes for which 
they are employed. 

Their former uses for shelter, boats, armors, shields, etc., 
which have been mentioned before, are of course obsolete ; but 
modern demands far more extensive and in accord with our ad- 
vancing civilization have arisen, and new employments are all 
the while being discovered. 

Besides the domestic hides, large quantities are imported from 
the East and West Indies and from the Cape, but especially 
from South America. From the East and West Indies we re- 
ceive light dried bullock hides, called kips, which possess a 
greater or smaller value, according to quality and the thick- 
ness of the coating with which they are provided upon the flesh 
side. Dried kip-skins freed from flesh and prepared with arsenic 
are also brought from Java, the East Indies, and other places. 

Hides from Central Africa and the east and west coasts of 
Africa, as also from China, are used for upper leather. 

The conditions of temperature generally prevailing in South 
American countries, i. e., hot days and comparatively cool nights 
seem to impart to the hide of the cattle greater insensibility to 
sudden changes of temperature. 

The different varieties of South American hides are gene- 
rally known by the name of the port from which they are shipped. 
The best hides come from Buenos Ayres and Montevideo, both 
bringing in commerce about the same price. 

They differ externally in that the head of the Buenos Ayres 
hides is trimmed off rounder and the fore part is narrower than 



HIDES AND SKINS, 41 

in the Montevideo hides. A third variety, also imported from 
South America, is known as Kio Grande hides. They are less 
valuable than the above, being thinner on the neck and more 
uneven. They differ externally from them in being longer and 
more curled around the head part. 

The animals which roam along the Pampas and Llanos, or 
great plains, in herds of vast numbers, are, in addition to those 
owned by the extensive cattle owners or hateros, the stock 
whence the great quantity of hides used is annually derived. 
They are imported both in the dry state and salted, and produce 
a quality of leather ranking as has already been stated. 

Heavy hides are converted into sole, belt, and harness leather ; 
also into carriage coverings; medium weight hides are much 
used for upper leather, and the smaller and lighter kinds are 
made into leather, much used for skirtings and for enamelling. 
That which is used for some kinds of ladies' shoes and for 
bridle leather undergoes a bleaching process termed fair Jin- 
ished. 

Calf-shin is a principal material for the manufacture of upper 
leather for shoes and boots, and is also much used for book- 
binding. This leather, -notwithstanding its comparative thin- 
ness, excels in strength and flexibility, and for this reason brings - 
a comparatively high price. 

The German, and especially the Bavarian calf-skins, are much 
in demand. Dried calf-skins are imported from the East Indies 
and from South America. Russia exports large quantities to 
Germany and France. 

Sheep-shins are used for a lower grade of bookbinding, for 
bellows, whips, aprons, women's shoes, cushions and seat covers, 
linings and bindings of boots and shoes, gloves, leggins of dif- 
ferent kinds, and sometimes for trunks. 

When tanned in oil, sheep-skins form a good imitation of 
chamois leather, and at times they have been tanned with sumach 
and largely used for the imitation of morocco of all kinds ; this 
was especially so during the American civil war. Sheep-skins 
and split calf-skins are also sometimes employed to manufacture 
imitation of French kid and other varieties of morocco leather. 

Lamb-skins of very young animals, being of even thickness 



42 THE MANUFACTURE OF LEATHER. 

and possessing a fine and delicate grain, furnish an excellent 
glove leather. 

The various breeds of sheep, on accoant of the vast numbers 
in which their skins come into market, and the numerous appli- 
cations of sheep and lamb-skins, rank next to oxen in value as 
sources of leather. 

The importance of a breed of sheep for the purposes of the 
tanner is in inverse proportion to its value as a source of wool. 
The home supply is very extensive, and although they are capa- 
ble of making only a spongy, weak leather, the uses to which they 
are devoted are various, and their manufacture gives employ- 
ment to numerous hands. Tanned with bark they constitute 
bazils, and are used for making slippers and as bellows leather; 
but when prepared with alum and salt, or with oil, white 
leather, much emploj^ed for aprons and by druggists, and chamois 
leather result. Many are split, the upper or grain side being- 
tanned with sumach and dyed, then worked up as skiver^ roan, 
and morocco into pocket-books and hat linings, and the under 
portion being made into white leather and used very much by 
the chemist; but it is much the more general practice to reserve 
lamb-skins for the latter purpose. Sheep-skins are sometimes 
tanned with the wool adhering to them and made into mats. In 
Asia Minor a considerable trade rises from the preparation of 
lamb-skins for ladies' glove leather, for lining of morning gowns, 
for slippers, and for winter gloves. On the hides from Asia 
Minor the wool is kept for the purpose of retaining the warmth. 
Considerable difference may be observed in the quality of lamb- 
skins ; those from the animals killed shortly after being born 
are possessed of an exceedingly fine grain, and take a uniform dye. 
The same qualities are in a great measure retained by the skins 
till a month old, but from this period they begin to deteriorate. 
In the southern part of France and in Italy great numbers of 
lambs are killed averaging four weeks old, and the leather is 
prepared and employed as a substitute for kid leather. 

Goat-shins rank next in order of importance, the products 
which they yield being beautiful in texture, of great value, and 
of varied usefulness. Goat-skins are obtained mostly from the 
East Indies, the Cape, North Africa, South America, Mexico, 



HIDES AXD SKINS. 43 

Asia Minor, and the hilly regions of Europe, and form the most 
desirable material for gloves and morocco leather, and are exten- 
sively manufactured into blackened " grain leather" for uppers 
of ladies' shoes. Besides Swiss goat-skins, which are in special 
demand on account of their smooth grain, those from Mexico 
are also especially distinguished by their size and strength, being 
superior in this respect to those of the Bast Indies. 

Horse-hides and the skins of the other Equidse — the ass, zebra, 
quagga, etc. — have in modern times become very important raw 
materials for leather. These hides are sometimes used as a sub- 
stitute for those of cattle, and persons who are not acquainted 
with leathers probably unsuspectingly purchase articles made 
from this material. 

Boot-makers, of late, sometimes in large cities, make a spe- 
cialty of producing custom-made stock from this material, they 
so advertise it, and do not fail to find customers ; in fact, there 
are now a large number of gentlemen who much prefer it, and 
will accept nothing else. 

A large quantity of this material is imported from England, 
and, when it is intelligently tanned, the boots into which it is 
made are quite waterproof, easy to the feet, and in many ways 
very desirable; but when imperfectly tanned it burns and blis-- 
ters the feet. The chief consumption is, however, as cordovan 
or enamelled leather, the hides being split by machinery to reduce 
them to the adapted thinness. Horse-hides are likewise made 
into tawed, white, or alum leather, and are in this state used as 
aprons for certain classes of mechanics, and as thongs for the 
manufacture of common kinds of whips, and for sewing common 
harness, and also as a covering for base-balls. 

Leather made from horse-hides is also sometimes very desira- 
ble and useful for the manufacture of horse-collars, but for this 
purpose also the tanning should be intelligently done, otherwise 
it will form galls and blisters on the necks of the animals wearing 
them. 

Seal-shins obtained from Alaska and other Arctic regions are 
of great value for fur, and deprived of it, form a tough but 
porous leather, and "blacked on the grain," it has, of late, been 
used for the manufacture of light summer shoes. Common seal- 



44 THE MANUFACTURE OF LEATHER. 

skins are partly tanned with the hair, and used in that state for 
the manufacture of travelling bags, caps, aprons, etc. 

Hog-shins are of value to the tanner for the purposes only of 
making saddle leather, but travelling bags, portfolios, etc., are 
sometimes made from these skins. 

Dog-shin is thin, tough, and valuable, and is good for the pur- 
poses of making gloves or for tuhang. 

Porpoise-shin works into a soft, strong, and very durable 
leather, and is largely used as ties for gentlemen's heavy shoes. 

Hippopotamus and Elephant hides yield a leather of great thick- 
ness, when tanned resembling a board, and are used for buffing 
wheels in cutlery manufacture, and in the construction of imple- 
ments used for beetling in bleaching and washing cotton and 
woollen goods. 

Alligator-shins have for nearly thirty years been tanned into 
leather, and have formed an item in the trade lists of this coun- 
try, and the leather is now being much sought after in European 
markets. 

The industry was first started about 1855, and centred first at 
New Orleans, the raw skins being obtained from the rivers of 
Louisiana ; but at the present time the skins are principally ob- 
tained in Florida, and the tanning of them is quite a large and 
growing industry of Jacksonville. 

Some of the tanneries of Brooklyn, IST. Y., make a specialty 
of these skins; they also form an item in the stock of some of 
the tanneries in the State of Massachusetts. 

The young animals only yield the skins for leather-making, 
and the portions used are the belly and flanks, the back Avhich 
forms about one-third the skin is cut out, and the remaining por- 
tions are "green salted," great care being observed not to rot the 
tender portions between the scales. These skins are exported 
in large quantities to England, and are not uncommonly tanned 
there. 

Alligator-skins form a leather which has a scaly surface, and it 
is largely employed for fancy boots, shoes and slippers, and it is 
also much used for making pocket-books, hand-bags, and some- 
times large travelling satchels, cigar-cases, and a great variety 
of other small articles. 



HIDES AND SKINS. 45 

Kangaroo -shins are now largely employed in Australia for the 
preparation of leather. Wallaby and other marsupials native 
to that continent are also used. 

These skins are both tanned and tawed, the chief tanning agent 
being the mimosa bark, which is very abundant in Australia. 

The leathers which they produce are of an excellent quality, 
strong, and elastic, and are a first-rate rival in appearance to the 
kid of European tanners ; but, owing to the fact that the animals 
exist only in the wild state, the source of supply is limited and 
very insecure. 

Buffalo-hides are tanned like ox-hides, but they make an infe- 
rior quality of sole leather. When tanned in a particular way 
Avith oil, they constitute what is termed hiff-helt leather^ which 
is superior to the similar article made of cow-hides. 

Deer-shins are manufactured in large numbers into chamois 
leather, and also into glove leather, 

Sharh, and Rhinoceros-shins also find their way into the vat of 
the tanner, and into a market. 

Walrus-hides are tanned in England and employed for main 
driving belts for machinery. 

EEMOVING HIDES AND SKINS FROM ANIMALS. 

It happens only too often that the hides and skins of slaugh- 
tered animals, or of those that have died from natural causes, 
are not at once taken off, but left for days together on the car- 
cass. This is in the highest degree detrimental to the hides, as 
they acquire thin and defective spots, through the process of 
decomposition going on in the carcass, or the worms which are 
forming in the interior of the animal work destructively upon 
the hides. Great damage is also caused, although not of so 
grave a nature, if, in flaying, the work is not done with all due 
care. The bits of flesh and fat, which are often allowed to re- 
main adhering to hides and skins, become at once decayed and 
communicate decay to the skin ; which is injured or eaten away 
in spots, becoming, consequently and subsequently, very thin or 
even worn into holes. Such damage is noticeable in a more 
especial manner after manufacture, when the leather is found 



46 THE MANUFACTUEE OF LEATHER. 

bad in appearance, or inoculated with dark spots, as is the case 
with colored leather. 

Leaving these defects out of the question, the suppleness and 
durabilit}^ of the leather itself will be injuriously affected, if the 
skins are not suitably and carefully treated in drying and hang- 
ing up, by the premature shrinking and imperfect drying of the 
material. 

An evidence that the evils just mentioned, arising from im- 
proper treatment, are of more importance than is generally 
thought, is shown in the fact, that the sheep-skins received in 
the summer season often jneld barely one-third of a material 
perfectly adapted to the fabrication of imitation morocco leather. 

In view of these evils, and in order to promote the interests 
of the leather trade, the following points are urgently recom- 
mended to the producers of the raw material in flaying hides 
and skins : — 

1st. Immediately after the death of the animal the hide or 
skin should be carefully taken off'. 

2d. The fleshy or fatty portions still adhering to the skin 
should be detached down to the smallest pieces. 

3d. The hide should, without the least delay, be hung up in a 
very airy place, one not exposed to dampness, with the hair side 
inward, so that a draught of air may' play upon the entire length 
of the flesh side of the hide. 

4th. In order to prevent the hide from shrinking, the head 
and tail ends should be stretched out, and nailed to the pole. 

5th. The hoofs and legs should be spread with skewers on 
both sides. 

6th. The flaying of the hide should not be intrusted to inex- 
perienced persons; for, unless a certain dexterity is brought 
into this operation, the value of the skin will be considerably 
lessened. 

Only by observing these directions can skins and hides be 
properly dried, and delivered free from defects, suitable for val- 
uable use. 

The benefits that will accrue to the entire leather trade by 
following such a course, cannot be rated too highly; for not 
only will it secure a serviceable material to manufacturers, but 



HIDES AND SKINS. 47 

also a large quantity of hides and skins will be saved from 
destruction, and the market will be better and more fully sup- 
plied. A further consequence will also be that a better manu- 
factured article will be produced, and lower prices established 
for hides. 

SELECTING- HIDES AND SKINS. 

Considerable difference is observed in the thickness and 
quality of the skins of various animals, even in those of the 
same class, owing to circumstances connected with the food, 
age, variety of breed, the state of health, and even the period 
of the year when they are slaughtered. Thus, large oxen are 
well known to afford hides which are tanned into thicker and 
heavier leather than bulls or cows, especially if the latter be 
old and have had several calves. Bull-hides are coarser-grained, 
and thinner in the back than those of oxen and heifers, or 
young cows, but much denser in the neck and parts of the 
belly. It would also appear that when cows have repeatedly 
calved, the skin becomes distended and thinner, and. does not, 
therefore, afford as heavy a sole-leather as that of younger ani- 
mals. Again, hides of animals, dying in a state of disease, are 
found to be much inferior to those of healthy ones of the same 
class, although the apparent difference is not very marked be- 
fore tanning. 

No very definite criteria are known to guide the purchaser in 
distinguishing the quality of hides and skins. If the hide be 
thin, flabby, soft, and will not bear handling, then such a one 
will not make good leather; but should it present the opposite 
quality, it may confidently be expected to be a good article. It 
has been remarked of sheep, that the finer wool varieties have 
inferior skins; also that the skin gains in thickness and quality 
considerably in the course of a few days after shearing. 

The proper selection of skins, according to size, thickness, 
and strength, which decide the value of a hide for the prepara- 
tion of certain varieties of leather, is a difficult problem for the 
manufacturer, there being not only great differences in the vari- 
ous kinds of hides, but also great inequalities in those of one 



48 THE MANUFACTURE OF LEATHER. 

species, according to the sex and age of the animal, and the 
manner in which it had been fed. Many breeds of cattle fur- 
nish, for instance, hides possessing a certain thickness towards 
the sides, while those of others are thinner, or, as the tanner 
calls it, "fall off toward the sides." 

In commerce a distinction is made between hides and skins, 
as has been stated, though it is not sharply defined, as it depends 
simply on the thickness of the materials. 

In the buying and valuation of hides the following principal 
points are generally taken into consideration : — 

Thin hides, of unequal thickness, are of less value than full 
and even hides. Young hides are preferable to old ones, as the 
fibre in the latter is generally thicker and less flexible. 

There is besides a difference in favor of the hide of a cas- 
trated over an uncastrated animal of the same species. 

Hides of animals having died from contagious diseases should 
be entirely rejected, or at least handled with the greatest care. 
Many a tanner has suffered severe sickness, or even lost his life, 
by careless handling of hides derived from animals afflicted 
with inflammation of the spine. The poisoning, as is well 
known, is effected by the transmission of a fungus {Bacterium 
anthrax)^ which, when placed upon abrasions of the skin, pro- 
duces malignant carbuncles, which in most cases are fatal, if 
help is not quickly rendered. Besides the hacterium anthrax, 
there are other infectious substances which may produce blood- 
poisoning. 

We will here state that tanneries and other places where skins 
are stored should be frequently disinfected with a two to three 
per cent, solution of carbolic acid, and kept as clean as possible. 
It may also be recommended to the workmen occupied in these 
places to use the same solution of carbolic acid as a wash against 
infection. 

Independent of the dangerous properties, disinfection and 
thorough cleansing of the storerooms would expel the foul 
odors produced by products of decomposition and putrefaction, 
prevalent in so many tanneries, and contribute materially to 
the preservation of the hides. 



HIDES AND SKINS. 49 

FRAUDULENTLY INCREASING THE WEIGHT OF HIDES BY THE 
EMPLOYMENT OF SULPHURIC ACID. 

It is well known that leather "plumped" by the agency of 
sulphuric acid is not only brittle, but readily absorbs moisture, 
and sometimes butchers profit by this property in the sulphuric 
acid of facilitating the absorption of water by the skin ; thus, 
before delivering the hide they steep it for a few hours in a 
very weak solution of this acid; the hide looks well and its 
weight is increased, notably by the amount of water absorbed. 
This fraud is generally disccjvered at the "plumping" only, 
when the hide, having been previously swollen, does not increase 
in thickness, and especially after the tanning, when it is found 
that the yield of the leather is in this case by far inferior to the 
quantity which might have been expected, according to the 
original weight of the hide. A cabbage leaf, or a piece of blue 
litmus paper is sufficient to detect this fraud ; when applied to 
the hide the paper takes the tint of onion-peel, so well known. 
It is true that the hide which has not been tampered with, has 
also an acid reaction, due, probably, to the small quantity of 
lactic acid which is found in almost all fleshy parts. But in 
this second case, the leaf, or 'the litmus paper becomes only of a 
very weak, vinous color. The taste of the hide is also a sure in- 
dication. By also steeping a piece of the hide in distilled water, 
to which is then added some chloride of barium, we obtain, if 
there is fraud, a notable precipitate of sulphate of baryta; with 
the natural skin a very faint suspicion only is obtained. 

PRESERVING HIDES. 

Mode of Salting. 

Delane's method, which is that generally employed, consists 
in laying the hides open upon the ground and sprinkling the 
flesh side with salt, more liberally at the edges and on the spinal 
portions than on any other parts. They are then folded or 
doubled lengthways down the centre. The remaining folds are 
made over each other, commencing with the shanks, then the 



50 THE MANUFACTUEE OF LEATHER. 

peak of the belly upon the back, afterwards the head upon the 
tail part, and tail part upon the head, and, lastly, by doubling 
the whole with a final fold, and forming a square of one or two 
feet. This being done, they are then piled three and three to- 
gether and left until the salt has dissolved and penetrated their 
tissue, which generally requires three or four days. Thus pre- 
pared they are sent to market. 

Skins may be dried even after having been salted by stretch- 
ing them upon poles with the flesh side uppermost and exposing 
them to dry air in a shady place. 

Ten pounds of salt in summer and somewhat less in winter 
are requisite for each skin of ordinary size. 

In place of salt, disodium sulphate (Glauber's salt) has been 
recently recommended as having the advantage of not decreas- 
ing the green weight and being as good a preservative as com- 
mon salt, which decreases the weight of the green hides twelve 
to fourteen per cent, by withdrawing endosmotically water which 
runs off as solution of common salt, which, by the use of Glau- 
ber's salt, is fixed by the formation of crystalline sodium sul- 
phate. 

Besides the two materials mentioned, all kinds of antiseptic 
substances, such as wood vinegar, carbolic acid, mixtures of 
glycerine and carbolic acid,^ and recently even salicylic acid, 
have been proposed and occasionally used for preserving hides, 
though generally again abandoned for common salt as being the 
most simple and the cheapest means. 

Composition for Impregnating Hides and Shins and Preserving 
them in such condition as to he capable of being unhaired at any 
subsequent time by a simjple immersion in water. 

This is a compound patented by Moret, who claims that it 
enables hides and skins to be preserved for transport or storage 

1 We will here briefly mention a proposal according to which the flesh side 
of the green skin is coated with a mixture of 90 parts of crude dark glycerine 
and 10 parts of 50 per cent, carbolic acid applied with a whitewash brush, after 
which the skins are packed in boxes and packages. When the skins are to be 
worked they are freed from the preservative by washing, and then treated in 
the same manner as green skins. (Der Grerber, 1876, 527, and Wagner's 
Jahresberichte, 1877, S. 984.) 



HIDES AND SKINS. 51 

in such, condition that while the hair remains firm until it is 
desired to remove it, the hides and skins may be immediately 
unhaired at any subsequent time by a simple steeping in water; 
that is to say, they are impreguated with the depilatory agent 
and with a suitable preservative, so that, while protected by the 
latter from dry-cracking or putrefaction and from the attacks of 
insects, the former, being already contained in the pores of the 
skin or hide, is brought into such intimate contact with the 
hair follicles or glands as to act with immediate effect thereon 
as soon as the hide or skin is plunged into water, loosening the 
hair and enabling it to be removed with ease. 

To prepare the composition for this purpose : First, make a 
strong solution of American potash, or ordinary caustic potash, 
and heat to from about 180° to 200° F. Then add (stirring the 
composition well meanwhile) realgar in powder in the propor- 
tion of about two ounces to three and a half ounces for each 
pound of potash employed. There may also be added quick- 
lime in the proportion of three ounces, five ounces, or seven 
ounces for each pound of potash, the precise proportions in each 
case depending on the kind of potash used, and on the manner 
in which the composition is t9.be applied or used. The quick- 
lime may, however, be dispensed with altogether when the pot- 
ash is sufficiently caustic without it, the quicklime being only 
used when and in such quantities as it may be absolutely required 
to effect this object. The composition is allowed to settle and 
the clear liquor is decanted off'. This clear liquor is diluted with 
water until it marks 10° Baume. Also make separately a solu- 
tion of American potash in water at from 8° to 15° Baume, to 
which add thirty grains (or more) of salicylate of soda or other 
preservative salt for every hundred weight of the clear liquor 
above mentioned at 10° Baumd. These solutions are then 
poured together. The composition thus produced is applied, 
either with a brush or mop, to the hide or skin, or by immer- 
sion, the hides or skins being either left in this state or dried, 
according as they are to be kept a greater or less length of time. 
In the dry state it is claimed that they may be kept for an in- 
definite period, and may be at any subsequent time restored to 
their original green and natural condition by simply steeping 



52 THE MANUFACTURE OP LEATHER, 

them for about twelve hours in water, whereupon the hair and 
scud may be immediately removed with ease without further 
treatment with chemical agents. 

This mode of preservation, it is claimed, renders unnecessary 
the injurious liming or other treatment for unhairing. 

A Liquid for Curing Hides ^ composed of Pyroligneous Acid^ in 
ivhich are dissolved Aloes and Alum, or their equivalents. 

This compound, patented by Eock, is as follows : — 

To one gallon of pyroligneous acid, add about one ounce of 
aloes and two ounces of alum, both finely powdered, mixed, 
and dissolved in the acid. This liquid being kept in an ordinary 
tank or vat, the hides are soaked in it for from four to ten 
hours, then taken out and drained, when, it is claimed, they are 
ready for shipment. 

Hides so cured may also be unh aired without liming or sweat- 
ing in the sweat-box. By piling them in a room of an ordinary 
temperature for three or four days, it is claimed, they will shed 
the hair so perfectly that they may be put into the tan vat 
directly afterward ; but, if sweated in the sweat-box, the over- 
sweating which would render any other hide useless, it is claimed, 
will not injure this hide in the slightest degree, owing to the 
solidification of the fibres, in consequence of the curing. 

For upper leather and harness, which tanners sometimes pre- 
fer to lime for unhairing, the inventor states that he usually 
packs the hides with salt, i.e., after the hide is cured and drained ; 
so that there should not be any surplus moisture, he sprinkles 
the hide lightly with fine salt and then bundles it up. The ob- 
ject of this is that the salt should refrigerate the hide to a cer- 
tain extent, and thus keep the hair fast. 

There are also other ingredients which may be employed with 
the pyroligneous acid for the purpose of preserving the hides 
from bugs, worms, etc. For instance, one dram of arsenious 
acid mixed with one dram of carbonate of potassa, and boiled 
in about half a pint of water until it is dissolved, and then 
added to one gallon of pyroligneous acid. 

Sulphate of copper, borax, sulphate of iron, and others may 



HIDES AND SKINS. 53 

be used ; but the inventor states that he has found that the first 
compound answers every purpose. 

Sahathe and Jourdan's Process. 

The preserving substance employed in this method is metallic 
soap insoluble in water, for instance, with the base of zinc, lead, 
copper, albumen, iron, manganese, or two or more of these soaps 
mixed together. 

Fatty materials such as resins or bitumina chemically com- 
bined or merely mixed in various proportions with oxides or 
metallic salts are also employed. 

Napier''s Process. 

The patentee claims in this process the use of carbolic acid, 
or of creasote in any form, and either alone or in combination 
with each other and with other substances, such as a metallic 
salt, glycerine, etc. 

Sacc's Process. 

This process has for its object the preservation of green hides 
by the employment of chrom-ic acid, pure or combined. The 
hides to be preserved are soaked in a solution composed of 1 
part of bicarbonate of potash and 10 parts of warm water. 

The time during which they are soaked in the solution is 
usually about twenty-four hours, but it may be more or less, 
according to the temperature of the atmosphere, the thickness 
of the skins or hides, and their dryness. It is claimed that this 
simple operation is sufficient for the preservation of the hides 
or skins. There can be used in connection with bichromate of 
potash, certain salts, such as those of alumina, zinc or copper, 
pyroligneous acid, common salt, etc. 

Wicker sheiiner'' s Process. 

This compound for preserving hides is prepared by dissolving 
in 4:\ pints of water over fire, 50 grams of common salt, 10 
grams of saltpetre, and 14:0 to 160 grams of alum, when the 
solution is allowed to cool ; after which dissolve in 200 grams 
methylalcohol, 20 grams of carbolic acid, then mix this second 



54 



THE MANUFACTURE OF LEATHER. 



solution with the first one and add one gram of thymol. Owing 
to the preponderance of alum in this solution it needs to be 
stirred up every time it is used as the alum is apt to settle. 
The compound is applied with a sponge or brush, or the hides 
may be dipped into it. 

List of all Patents issued by the Government of the United States of 
America for Preserving Hides, from 1790 to 1883 inclusive} 



No. 


Date. 


Inventor. 


Eesideaoe. 


58,036 


Sept. 11, 1866 


E. Sabath^ and > 
L. Jourdan, ^ 


Paris, France. 


59.251 


Oct. 30, 1866 


H, Napier, 


Elizabeth, N. J. 


75,794 


March 24, 1868 


L, S. Robbins, 


New York, N. Y. 


86,808 


Feb. 9, 1869 


J. P. Bridge, 


Boston, Mass. 


112,285 


Feb. 28, 1871 


A. Rock, 


New Orleans, La. 


118,746 


Sept. 5, 1871 


A. Rock. 


New Orleans, La. 


171,177 


Dec. 14, 1875 


F. L. C Sacc, 


Neufchatel, Switzerland. 


246,260 


Aug. 23, 1881 


J. Wickersheiraer, 


Berlin, Germany. 


281,287 


July 17, 1883 


J. L. Moret, 


Paris, France. 



COMMERCIAL CLASSIFICATION OF HIDES. 

All hides sold in the American market are classified as dry 
flint, dry salted, green, green salted, and part cured. 

Dry fiini is a thoroughly dry hide that has not been salted. 

Dry salted is a thoroughly dry hide, having been salted while 
green. 

Green hides are those which are sent in just as they come 
from the animal after being slaughtered. 



' The first American patent system was founded by act of April 10, 1790, and 
it is a source of great regret that no well-preserved history of Airierican inven- 
tions dating from that time is in existence, and that no classified list of models 
which were in the Patent Office at the time of the fire in 1836 can be obtained. 
The earliest date that can be reached is January 21, 1823, and that is only par- 
tially complete. After the fire in 1836, the United States Government adver- 
tised for the patents which had been issued prior to the conflagration, and in 
this way numerous copies of the earlier patents were secured. This explana- 
tion is necessary in order to make plain the reason why certain of the numerous 
lists of patents in this volume contain some patents dating from 1836, and other 
of the lists contain patents dating from a much earlier period. 



HIDES AND SKINS. 55 

Green salted are those that have been salted and are thoroughly 
cured. 

In green salted hides and skins, those which weigh less than 
8 pounds are called deacons ; 8 to 14 pounds, calf ; and 14 to 25 
pounds, if they are plump, kip ; bat if they are thin and poor 
they are called runners or murrains, and are sold at two-thirds 
the price of good kip ; all weighing in excess of 25 pounds are 
called hides. 

Green salted hides are understood to be thoroughly cured, 
free from salt, dirt, meat, water, horns, tail bones, and sinews, 
and before being weighed all such substances are removed, or a 
proper reduction is made from the weight. 

Part cured hides are those that have been salted, but not 
sufficiently long to be thoroughly cured. 

All stag, tainted, aod badly scored, grubby, or murrain hides 
are called damaged, and must go at two-thirds price, unless they 
are badly damaged, when they are classed as glue stock, aad sell 
at a much lower figure. 

When hides are branded a deduction of about ten per cent, is 
made on all of them. 

In dry hides there are other kinds of damaged, such as sun- 
burned, weather-beaten, or moth-eaten. 



56 THE MANUFACTURE OF LEATHER. 



CHAPTEE II. 

SYNOPSIS OF THE HISTORY OF TANNING — COMMERCIAL 
VARIETIES OF LEATHER. 

SYNOPSIS OF THE HISTORY OF TANNING, 

An art may continue for a time slowly progressive, bat can- 
not reach its highest point until its limit be precisely defined. 
An excellent means by which to improve an art consists in ex- 
plaining its origin and progress and in pointing out the end to 
be attained, and the bounds within which it must be confined. 
Without this precaution, we exhaust ourselves in single and un- 
connected researches, without reference to each other, and the 
knowledge which we acquire is dissipated and loses in force as 
it recedes from the common focus. 

A small number of principles and a great mass of conclusions; 
this is the history of all arts, all sciences. The principles must 
rest upon reliable facts derived from experience and observation ; 
but neither a compiler nor an author can render all conclusions 
and explanations. The principles are not numerous and are easy 
of comprehension, but the conclusions arising from them are 
innumerable, and lucidity is only to be achieved by placing them 
in order under the general laws to which they respectively be- 
long, and, therefore, a judicious classification is requisite. 

"We will first give nearer data upon the origin and development 
of our system of tanning, and subsequently consider minutely 
and singly each step in the tanning, currying, and finishing of 
leather, and the different methods and systems in our tanneries 
at home and abroad, keeping constantly in view the statistics of 
the foreign leather trade and manufacture as compared with our 
own. We beg to go back some centuries in history, and we will 
be convinced that the products of our trade were known in the 
time of Moses; for at that period leather carpets were already 



SYNOPSIS OF THE HISTOEY OF TANNING. 57 

used in tents; these we may at present still meet with among 
the Arabs, Colored leather seems to have been common, for 
Ezekiel speaks of fine red leather, which was probably our splen- 
did red morocco. 

In 593 B. C, in describing the brilliant dresses and horse har- 
ness of the Babylonians, the Chaldeans, Pekods, Shoas, Koas, 
and all the Assyrians with them, girded with girdles upon their 
loins, clothed most gorgeously, all of them captains and rulers, 
great lords and renowned, riding upon horses, the trappings of 
which were replete with rich and beautiful colors, Ezekiel con- 
veys some idea of the grandeur which prevailed and the brilliant 
color of the dyed leather in use at the time he was prophesying 
the ruin of the two great kingdoms. Leather was also used in 
the remotest ages by the Israelites as a material to write upon, 
for they used strips made of leather for this purpose. Accord- 
ing to the testimony of Herodotus, the ancient lonians wrote 
their annals upon sheep-skin, and the ancient Persians, likewise, 
according to Diodorus of Sicil}^ 

Herodotus also tells us that the ancient Libyans wore leather 
clothing; the Ichthyophagists on the banks of the Araxes 
dressed themselves in seal-skins, and in the time of Alexander 
the wild inhabitants of Geodrosia used the hides of animals for 
clothing and covered their dwellings with leather. 

For many years leather was used by the Greeks in the con- 
struction of ships; especially by the Phoenicians, who originally 
inhabited an arid, sandy corner of the earth, between the Eed 
Sea and the Mediterranean, where the soil was not favorable to 
the growth of timber, and they were obliged to supply its place 
by covering their boats, constructed of willows woven together, 
with leather or hides, which even thus early were subjected to a 
certain amount of dressing. The ancient Germans, also, who 
lived on the sea-coast, and the original Britons, equally possessed 
this custom. 

Homer praises the splendid half boots of Agamemnon, and 
Hesiod recommends leather shoes lined with fur. 

Homer has perpetuated the name of a tanner who showed 
kindness to the beggar poet, and now after passing undying 
through the ages gone, we are charmed by his lines to-day, which 



58 THE MANUFACTURE OF LEATHER. 

are in praise of his friend, and of good cheer for the working- 
men who were employed in the tannery which he so frequently 
visited, and where he was at all times well received. 

That the preparation or tanning of hides was discovered cen- 
turies ago, and that the leather produced was employed for the 
same purpose as at present, is shown by the following old pro- 
verb, which is a proof that leather shoes were already worn at 
that time, viz. : " We must vot steal leather to give away shoes in 
God's name.'''' This refers to the legend of St. Crispin, who stole 
leather to make shoes out of it for the poor. In the old form,of 
speech, "To draw frovi the leather^'''' signified to draw the sword. 
In low Saxon the same expression signifies to undress. What- 
ever may be the facts, it is to be presumed that the most ignorant, 
races of antiquity, whose chief occupation was the chase, pos- 
sessed the knowledge of giving a certain preparation to the raw 
animal hides to protect them from decay, and to render their 
necessary clothing convenient. They were certainly driven to 
invention by necessity, and thus the origin of the art of tanning 
was probably the work of accident, like the invention of most 
of the other arts. To them, consequently, must the invention of 
the art of tanning leather be ascribed, although it must be con- 
ceded that this art owes its proper cultivation and perfection to 
more recent ages. 

Such is the synopsis of the historical origin of our leather 
trade ; but the gradual development and progress of technical 
tanning have been promoted and assisted by many, and among 
the most zealous are MacBride, St. Real.^ Proust.^ Hermstadt, 
Vauquelin, Ghaptal, Seguiii^ Desmond^ Von Meidinger^ AiJcin, 
and others. Attempts have been made to discover new 
methods by which hides and skins could be better tanned, and 
in a shorter space of time, than by the usual mode of treatment. 
In the year 1768 MacBride discovered the process of raising 
with diluted sulphuric acid (1 part acid to 400 parts water). 

Later great attention was attracted to the system of quick 
tanning, discovered in 1795 by Seguin, by which hides and 
skins were tanned in much less time than formerly. This new 
process was tested by experts, and found to be partially good 
and partially deficient. In 1801, Banks discovered the tanning 



SYNOPSIS OF THE HISTOEY OF TANNING. 59 

property of Terra Jcqwnica (Catechu), Since that time tannin 
has been discovered in a great number of plants, which will be 
enumerated in another chapter. 

The English discovered, in the last century, the art of var- 
nishing leather, which was soon after imitated in Grermany with 
complete success. 

Ballamy, Von Hildebrandt, Edward, and others introduced 
the art of preparing water-proof leather. 

Science has not done its duty in regard to the improvement 
of the art of tanning. There have been steps taken in the sav- 
ing of labor, which are of great importance ; but in all the long 
years that have passed since the union of tannin and gelatine 
was first demonstrated how little progress we have made ! At 
first it did seem to promise immediate results ; but failure has 
succeeded failure, and the fruit which should have resulted has 
not fully appeared, and all because of a lack of chemical know- 
ledge. 

If the production of tanneries has been increased and the 
time of their work shortened, it is owing not to the introduc- 
tion of new principles and to scientific theorizing, but to the 
use of improved apparatus for facilitating old processes. Take 
away our bark and hide-mills, improved leaches and vats, hand- 
ling and stuffing appliances and other improved constructions, 
our splitting, scouring, boarding, whitening, polishing, pebbling, 
and other modern mechanical inventions, and our steam-power 
so economically derived from the use of spent tan for fuel, turn 
us out of doors to work among the rude contrivances of a 
centur}^ past, and would the result of our labor show an extra- 
ordinary gain either in time or quality over that of our 
predecessors ? 

The modern appliances, of which American tanners are so 
justly proud, and in which they lead the world, are certainly 
ingenious and highly praiseworthy, and having taken a deep 
interest in all classes of mechanical improvements, that have 
been perfected by my countrymen, and upheld them before all 
nations, I would not for one moment be understood as depre- 
ciating their importance, or in the least to slight the intelligent 
enterprise of which they are the offspring. 



60 THE MANUFACTURE OF LEATHER. 

But it is skill, not force, chemical knowledge, not steam- 
power, which is principally in the future to accelerate and 
cheapen the process of tanning ; and the sooner the trade acts 
on this conviction, which every day's experience ought to 
strengthen, the better. If our present machinery can be super- 
seded by the discovery of more effective and economical 
methods, it will furnish cause for congratulation and none for 
mourning. Our inventors must aim to be good chemists as 
they are already good mechanics. 

With the analytical taste of the French and the Germans 
superadded to their great ingenuity and energy, what results 
might not be expected from their studies ? The field to be ex- 
plored is a broad one. Long as the art of tanning has been 
known to the world, not one step in its chemical practice seems 
to be complete. There is still room for iaquiry after tanning 
materials, and still a doubt whether tannin, or what is equiva- 
lent to tannin, may not be produced in quantity by artificial 
means. 

Especial attention is invited to all the vegetable, mineral, and 
artificial tannins which are to be hereafter described, not for 
experiments that have no knowledge of chemistry to direct 
them, but for those who are willing to acquire a thorough 
knowledge ^of any one of the materials themselves, and then 
supplement it with that of the chemical combinations which it 
is capable of forming. In this way only can further satisfactory 
progress be made, or the result of our experiment be of value. 
The hide itself should be examined and analyzed at every 
stage of its manufacture. Its structure cannot be too minutely 
scrutinized ; its preliminary preparation is a problem ; the 
nature of gelatine is a study ; the manufacture of ooze, simple 
as it appears, is not uniform ; the proper consistency and 
strength of the liquor are yet to be graduated and fixed. Most 
of all, the union of the tannin and the gelatine in the interior 
fibres is to be critically observed and facilitated by every possi- 
ble means. The object is, of course, to produce leather in less 
time and at less cost than heretofore. 

To these remarks the tanner will probably reply that he has 
neither taste, time, nor means to employ in chemical experi- 



SYNOPSIS OF THE HISTORY OF TANNING. 61 

ments. But if this be so, he can at least join his brethren and 
endeavor with them to eft'ect, by concerted action, that which 
it may be impossible for a single individual to accomplish. It 
is worth while to inquire whether our associations might not 
advantageously employ educated chemists to unlock for them 
the secrets of nature. 

There is no denying that our pathway to success winds up 
the hill of science. If we cannot travel it alone, we should 
secure guides, and accept whatever assistance is at hand. 

Of late some attention has been given in Europe to a system 
of tanning or tawing by means of chromium compounds patented 
by Dr. Christian Heinzerling, a German chemist. The oxidiz- 
ing power of chromate salts, and the deoxidizing effect of which 
organic matter has upon these salts, have long been recognized, 
and the knowledge of this action and counter- action has led to 
many attempts in the past to use chromates in tanning, but 
which have proved unsuccessful. It is now strongly claimed 
that the difficulties have been overcome by Dr. Heinzerling's 
process, which consists practically in the use of bicarbonate of 
potash, chloride of potassium, or chloride of sodium, and sul- 
phate of alumina. These are mixed together in one large stock- 
tank, from which the compound is drawn by means of a system 
of piping communicating with each pit, the quantity required 
to make the necessary strength of liquor; this at first, as in 
tanning with bark, is very weak ; but every few days it is sys- 
tematically strengthened, according to the thickness of the hides 
being tanned. The amount of chromatic acid ordinarily used 
amounts to from about 2| to 5 per cent, of the weight of the 
leather produced, and as the chromatic acid is not expensive 
the cost of the leather is greatly reduced. 

Light skins, such as sheep-skins and calf-skins, are tanned in 
less than one week, ox and buffalo hides in about two weeks, 
and walrus hides, more than two inches in thickness, in six 
weeks. 

After being tanned the hides, which at this stage are of a 
yellowish tint, like sumach-tanned leather, are dipped in chlo- 
ride of barium, which converts the soluble chromates on the 
surface into the insoluble chromate of barium. If any particu- 



62 THE MANUFACTURE OF LEATHER. 

lar shade of color is desired, it is then put on, and in general 
the hides are colored like ordinary leather. 

After being colored the leather is allowed to get nearly dry, 
when it is immersed in pure parafl&n wax and resin dissolved 
together in certain proportions. These materials with chloride 
of potassium, or chloride of sodium, and sulphate of alumina, 
aid in giving the necessary substance weight, and waterproofing 
to the leather. 

The hides are afterwards dried and brushed clean by suitable 
machinery, and when so finished the leather in appearance dif- 
fers but slightly from ordinary leather. 

Dr. Heinzerling claims as the meritorious and original fea- 
tures of his process the combined use of chromate compounds 
and fatty matter. 

The stuffing with fat or paraf&n of chrome leather, he main- 
tains, in the first place, reduces chromic acid to chrome oxide ; 
and secondly, the oxygen thus liberated in the substance of the 
hide oxidizes the fatty into acid bodies, which, uniting with 
the chrome oxide, forms a third insoluble compound mordanted 
in the fibre of the leather, rendering it at once supple and water- 
proof. 

Leather thus made has been reported by Mr. David Kircaldy, 
London, as very considerably stronger than the best bark-tanned 
leather he was able to procure. After steeping samples of it in 
cold water for six days, it has been found that the total quan- 
tity of tanning material extracted amounted to from .Ol-i to 
.135 per cent., while first-class bark-tanned leather treated in a 
similar way yielded 6.79 per cent. 

By boiling chrome leather in water for one-half hour, the 
loss ranged from .005 to .054 per cent. 

The .process seems to offer the means of utilizing classes of 
hides, such as sheep-skins, and very heavy hides, as those of the 
walrus, hippopotamus, etc., in a way that has not heretofore 
been found practicable by other processes. 

Sheep-skins in chrome tanning do not require to be pured 
and freed from their oleaginous constituents, and when finished 
by this process are no longer porous, but waterproof. 



COMMERCIAL VARIETIES OF LEATHER. 63 

They can be shaved and whitened like calf-skins, and it is 
claimed that they may be used for shoe purposes. 

Dr. Heinzerling's process is at work in various localities 
throughout Germany. For the United Kingdom and British 
colonies the patent rights have been acquired by the Eglinton 
Chemical Company of Glasgow, who, as manufacturers of 
bichromate of potash, have an indirect interest in the general 
development of the system. 

Although the method has not yet fully passed the critical 
stages of practical experiment, the products appear to be gain- 
ing the favor of men of great experience; and should the sys- 
tem fully meet the expectations of its originator and promoters, 
it cannot in the end fail to greatly cheapen many useful classes 
of leather. 

Dr. Heinzerling's system will be enlarged upon in the proper 
chapters of this work, in fact, his own language will be used, 
and no pains spared to fully describe his whole system of tan- 
ning. 

COMMERCIAL VARIETIES OF LEATHER. 

In the present section all the leathers known to commerce 
will be enumerated and slightly described, and the methods of 
their manufacture enlarged upon in the succeeding chapters of 
the work. 

The art of tanning is that by which animal hides and skins 
are converted into leather, a product possessing certain charac- 
teristic properties, being manageable and elastic after drying, as 
well as imputrescible, differing entirely from those of the original 
material, and eminently adapting it to the varied and useful pur- 
poses for which it is employed. 

These properties are of a physical nature, and varying with 
the kind of hide or skin employed, and the modifications of 
the process which it undergoes. 

Chemically considered, however, leather proper, whatever its 
kind, while not accurately speaking a chemical combination, is 
a compound of tannin and gelatine, possessing the all-desirable 
requisites of durability, pliability, inalterability, insolubility in 



64 THE MANUFACTURE OF LEATHER. 

water, and great power of resisting the action of cliemical re- 
agents, but of tliis subject we shall have more to saj hereafter. 

When mineral or earthy substances are used as the leather- 
making agents, the result is a compound of gelatine with the 
base employed, and is more or less indestructible, according to 
the nature of the material and the circumstances under which 
the combination takes place. 

Tawing embraces the preparation of leather by the action of 
mineral or fatty substances on hides and skins. The system of 
tawing is principally applied to thin and light skins of sheep, 
lambs, kids, and goats ; although in former times much leather 
was tawed for military belts, machine belts, etc.; for most light 
purposes, however, sumach-tanned or similar leathers are now 
usually considered to be much more durable, as well as applicable. 

By tawing a white, pliant leather is obtained with alum, salt, 
chromium compounds, fats, etc. 

This method was practised by the Eomans, for we read in 
Isidore of calcei (shoes) called allutse because the skin was soft- 
ened with alum, and the Eomans derived it from Africa. It 
appears to have been introduced into Hungary before the twelfth 
century. 

This leather is used principally by glovers and harness-makers. 
In Hungary, also, not long after the invention of tanning, cha- 
mois dressing was invented. In this method neither bark nor 
alum is employed ; the leather is simply dressed by rolling and 
other powerful operations, first with bran, and subsequently 
with animal fat (train oil). In order that the fat may the better 
penetrate, the grain side is cut away with sharp instruments. For 
this reason chamois leather is rough or velvety on both sides. 
The Hungarians were, in ancient times, especially celebrated for 
their white tanned leather, which was imitated in France as long 
as three hundred years ago. In chamois leather, the most 
famous is the fine, white, shining French and Dane's leather 
(made from lamb and goat-skins), from which the so-called kid 
gloves are made. 

The inconvenience of raw hides, and their roughness and 
hardness preventing their adaptation to the body, awoke reflec- 
tion ; men sought to discover the causes of these defects, as well 



COMMERCIAL VARIETIES OF LEATHER. 65 

as the means of remedying them, and thus arose with a gradual 
progress towards perfection the art of converting the raw hide 
into leather and for clothing, which mode of preparation is now 
called tanning. 

With an increase of population and wealth the greater became 
the demand for the necessities of civilization and luxury, and 
thus forced and attracted by necessity and gain, many experi- 
ments were made with a view to the improvement of tanning, 
until those excellent inventions were attained which have 
brought tanning to its present state of development. In these 
experiments the principal properties of tanned leather were kept 
in view. Attention was paid to the preparation of the hide so 
as to render it pliant and more impervious to moisture. 

The oldest method of tanning is red or bark tanning, or that 
in which, in addition to the wooden and iron scraping and rub- 
bing instrument used in the preparation or improvement of the 
hide or skin, lime-water, and astringent extracts from oak and 
other kinds of bark, or from other vegetable substances, are 
employed. It is called red tanning because the tanning sub- 
stances always contain more or less coloring matter, which dye 
the leather a more or less reddish color. 

The ancient orientals understood the art of preparing not 
only common leather, but even good, and often finely colored 
varieties, similar to our Morocco and Cordovan. Persian and 
Babylonian leather has been celebrated for many centuries 
back, as has been shown. Such leather was brought from 
Asia into Europe, first into Turkey, Prussia, and Hungary, 
and thence later to Grermany, Holland, England, France, Spain, 
etc., and these countries learned subsequently to manufacture 
leather themselves. In the first centuries of Christianity, the 
Turks, Eussians, and Hungarians were the most celebrated tan- 
ners; subsequently England, the Netherlands, and Spain en- 
deavored to equal them. 

Among fine leathers of foreign origin. Cordovan, Morocco, 
Shagreen, and Russia leathers have been especially famous. Cor- 
dovan, a soft, small-grained, colored leather, had already been 
prepared by the ancient Orientals. Its name is derived from 
the Spanish city of Cordova, where it was probably fii^&t iatro- 



QQ THE MANUFACTURE OF LEATHER. 

duced into Europe, and where, for a long time afterwards, it 
was chiefly manufactured. It. enjoyed a great reputation in the 
eleventh century, when the most distinguished persons wore 
shoes of Cordovan leather. The French name for shoemaker, 
"(7or(ioww{er," appears also to be derived from this leather. The 
best qualities have been made in Constantinople, Smyrna, and 
Aleppo. The best known German Cordovan is the Bremen 
variety. 

From the gradual improvement of Cordovan was engendered 
Morocco^ called also Turkish and Spanish leather, a still hand- 
somer leather than Cordovan. This beautifully colored and 
brilliant leather has been most excellently manufactured in 
Morocco, in the Levant, in Asiatic and European Turkey, in 
Krim Tartary, in Aleppo and Smyrna, and in the Island of 
Cyprus, and very well also in Eussia, Poland, Hungary, and 
Spain, but especially in England, France, Holland, Switzerland, 
and Germany (in the latter country at Offenbach on the Main, 
and Calin, in Wurtemberg). 

Morocco leather manufacture has been developed to a great 
extent in our own country, and with us the leading place for 
its production is Philadelphia, Pa., Newark, N. J., ranking 
next ; but Wilmington, Del., and Lynn, Mass., are also produc- 
ing it in large quantities. 

In contrast to our advancement in this line of production, the 
past fifteen years has witnessed the gradual but now complete 
destruction of not only Morocco, but also chamois leather man- 
ufacture in Eussia, although in other branches of tanning the 
value of productions has for the same period increased nearly 
250 per cent., and the number of tanneries at the present time 
is not less than 3800 in Eussia. Tanning is one of the most 
widely spread and best developed of Eussian industries, being 
represented in fifty-nine of the sixty Eussian governments, and 
working up in 1879 more than 7,000,000 hides (43,000 poods) 
and 741,000 goat and lamb skins, the latter being dressed more 
largely in the governments of Valadimir, Odessa, Vologda, and 
Kasan. 

Russia's wealth in fur-bearing animals, together with climatic 
conditions, rendering furs a matter of necessity, have given the 



COMMERCIAL VARIETIES OF LEATHER. 67 

trade of dressing these skins a development beyond that of other 
countries, and it is very much to be regretted that the branch 
of furriers proper had not been included in the statistics. 

Shagreen (in Turkish, Sagri, and Persian, Sagre) is chiefly 
celebrated for its hardness and strength, and for the peculiarity 
of the grain side, which appears as if covered with globular 
granules; it is also of eastern origin. The best shagreen has 
been made in Persia, Constantinople, Algiers, and Tripoli. The 
production of the small globular granules on the grain side was 
for a long time kept secret. We were first informed many 
years since by the celebrated traveller, Pallas, that they were 
produced by stamping the hard seeds of the wild orach [Ghe- 
nopodium album) into the hide, spread on the ground ; the 
seeds were afterwards knocked out and the hide scraped on the 
indented side and soaked in water for two days, in order to raise 
bulbs where the indentations existed. There is another descrip- 
tion of shagreen totally different, made from fish skin, called /?s/i- 
skin shagreen ; it is used for covers, wood polishing, etc. 

Russia leather is a strong and pliant leather, generally red or 
black, with a peculiarly penetrating odor, owing to the peculiar 
smell of oil of birch, and was undoubtedly invented by the 
ancient Bulgarians. It is only within comparatively late years 
that we have learned the mode of preparing this leather. Among 
other things, we first perceived that the peculiar odor arose 
from the birch oil which was rubbed into the leather. Inuften^ 
the German name of this leather, is derived from the Bulgarian 
word '•'•Jufti^'' a pair, as the Bulgarians, when they colored hides, 
always sewed them together by pairs in the form of a bag, with 
the grain side inwards ; the coloring liquor was then poured in 
and the hides kept in motion. The best Eussia leather has 
been made in various Eussian and Lithuanian provinces. 

But so rapidly has our own country developed the production 
of Eussia leather that we are manufacturing about all the leather 
of this kind which we consume, Philadelphia and Newark being 
with us the chief places for its manufacture, 

Eussia leather was formerly much employed in this country 
for bookbinding ; but its use for this purpose has been aban- 
doned by our principal librarians, and its place superseded by 



Y^ 



68 THE MANUFACTUEE OF LEATHEE. 

red-colored Morocco for this purpose. The Eussia leather bind- 
ings on the books would decay, and finally possess no greater 
strength than so much common brown paper. In the English 
libraries, the climate being more moist than with us, the use of 
Russia leather for bookbinding is still continued to a moderate 
extent, as the destruction is not so rapid as with us. 

Hungarian Leather. — The art of dressing leather upon the 
so-called Hungarian method, was first brought from Senegal, in 
Africa, and made known to us in the middle of the sixteenth 
century by one Buscher, the son of a tanner in Paris. At that 
time leather was common in Hungary, and that dressed there 
was very highly esteemed. In the year 1584, two German 
tanners named Lasmagne and Aurand came to Neuchatel in 
Lorraine, where they worked at their trade ; from thence they 
went to St. Diziers, in Champagne, and finally to Paris, where 
they prepared very good leather. 

In this process mineral salts are substituted for vegetable 
extracts. The hides are first treated with a mixture of alum 
and common salt, by which a portion of the sulphate is con- 
verted into the chloride of aluminum, the hides being kept 
supple by an excess of salt. 

The fleshing and scraping processes are proceeded with as in 
the ordinary modes of tanning, but the hair is removed by 
shearing instead of liming. 

The first alum bath usually contains alum 7 pounds, salt 4| 
pounds, water 8 gallons, for each hide of 85 pounds weight. 

The whole process of the manufacture of Hungarian leather 
will be described later in a separate chapter. 

Parchment was known long before the invention of paper; 
for sheep and goatskins were used to write upon in the time of 
Herodotus. The name is derived from the city of Pergamus, 
in Asia Minor, where it was excellently manufactured. The 
best parchment is prepared from calfskin, and inferior qualities 
from sheep, goat, ass, and pig skins. The fine virgin ■parchment 
is made from the skins of new-born lambs. 

Artificial parchment, which was invented in England, consists 
of linen, cloth, or paper, which is tightly stretched, and then a 
paste composed of gypsum, white lead, powdered lime, water, 



COMMEECIAL VARIETIES OF LEATHER, 69 

and parchment glue, is laid on with a brush four times ; it is 
then smoothed with pumice-stone, and lastly steeped in a bright 
oil varnish. 

The use of parchment is not extensive; beyond the ordinary 
purposes it is sometimes used for deeds, for printing, for 
diplomas, for organ bellows, and for sieves, and in England for 
sounding boards in stringed musical instruments. In Germany 
it is principally manufactured at Bentheim and Schuttorf in 
Hanover, and also in Augsburg, Nuremberg, Breslau, and 
Dantzic. Holland, England, and France manufacture excellent 
parchment. 

Alum leather is produced by tanning or tawing the skins 
white by a solution of alum or salt, and it is the same leather 
which has been before mentioned as Hungarian leather. 

Bazil is sheep-skin dyed with bark and used for making 
slippers, 

Buff leather is so named from the huffe or wild bull of Poland 
and Hungary ; it was used for armor, and tanned soft and white, 
and in Europe it is yet used for sabre belts and cartridge boxes. 

Chamois^ shammy, or shamoy leather was originally prepared 
from the skin of the chamois^ but the skins of other goats, and 
even of sheep, are now dressed in the soft manner, and furnish 
skins for carriages, polishing, for gloves, and other purposes. 

Enamelled leather is leather split to the required thickness, 
and then subjected to two operations; the first to render it 
impermeable to the varnish, and the other to coat it with varnish. 
The hides used are those of kip, calf, ox, or horse, and are 
rubbed on the grain or flesh side with three coatings of boiled 
linseed oil mixed with ochre or ground chalk, and dried after 
coating. The surface is then pumiced, treated ^with the same 
material of a thinner quality in several applications. Succes- 
sive layers of boiled linseed oil, and of this oil mixed with 
lampblack* and turpentine spread on with a brush, are laid 
over the thus prepared surface. The surface which has become 
black and shining, is varnished with copal and linseed oil con- 
taining coloring matter, which will be explained at length in the 
chapter on patent and enamelled leathers. 

The leather is curried expressly for this purpose, and particu- 



70 THE MANUFACTUEE OF LEATHER. 

]ar attention is observed to keep it as free from grease as pos- 
sible. It is sometimes used for boots and shoes, but most 
largely for carriage upholstery and similar purposes. It was 
first manufactured for carriage tops by David Crockett, of New- 
ark, N. J. Previous to this, oil-dressed leather, presenting the 
appearance of harness leather, was used for this purpose. 

Fair leather is subjected to a bleaching process and. is then 
finished in the color imparted by the bark, and is not speci- 
fically colored. 

Juncten is a name by which Eussia leather is sometimes called. 

Japanned, patent^ and varnished leathers are usually the same 
as enamelled leather, and the first made in this country was in 
1818, by Seth Boyden, of Newark, N. J. 

Oil leather is curried in oil, the usual medium being fish-oil, 
with or without potassa, which is employed in alternation with 
drying. Fulling, graining, and pummelling are employed, fol- 
lowed by coloring, stretching, and surfacing. 

Roan is a leather made from sheep-skins in imitation of 
Morocco, except the grain, and is used for bookbinding. 

Russet is leather finished except the coloring and polishing, 
the tanned hides being stored in this condition in order to be com- 
pleted in any desired manner, as the future demand may suggest. 

Saffian leather derives its name from Saffi or Asfee, as it is 
called by the natives properly, and anciently Soffia, which is a 
city of great antiquity belonging to the province of Abda, and 
was built by the Carthagenians near Cape Cantin. 

This leather is produced from goat-skins, and is but a sub- 
name for Morocco. Another leather made near Saffi, in Morocco, 
is the Mogador leather, whicli is also a sub-name for Morocco 
leather, and derives its name from Mogador the capital of the 
fertile Moorish province of Haba. Large quantities of goat-skins 
are exported from Mogador, which are mostl}^ brought there 
by caravans from Timbuctoo and the Soudan. Quite a large 
amount of Morocco leather is produced at Mogador, chiefly of 
that rich yellow color of which slippers are so universally made. 

Shiver is a thin split of leather used for hat linings, sales-cases 
for jewelry, etc. 



COMMERCIAL VARIETIES OF LEATHER. 



71 



S-plit-leather is that which has been split in a machine for sepa- 
rating the grain from the flesh side. 

Sometimes it is done to lighten a leather, and at other times 
to make two thicknesses, both of which are utilized. 

Wash-leather is a skin soft-dressed and suitable for polishing, 
and for making specie-bags, pantaloon and overcoat pockets, 
also for cleaning metals, plate, and highly-polished articles. 

Whang is a tough leather made from the skins of calves, dogs, 
ground-hogs, etc., and is used for bag-strings, whip-crackers, 
belt lacings for machinery, and other occasional purposes. 

White-leather is the same as tawed-leather ; the process leaving 
the leather white, differing thus from that tanned by ooze. 

In commerce the following names are applied to leather: — 



Alligator-leather. 

Alum-leather. 

American-leather. 

Backs. 

Band-leather. 

Bazil. 

Belt-leather. 

Bindings. 

Bridle-leather. 

Bronze-leather. 

Buckskin-leather. 

Buffalo. 

Buff-leather. 

Butts. 

Calf-skin. 

Card-leather. 

Chamois-leather. 

Collar-leather. 

Cordovan-leather. 

Curried-leather. 

Deer-skin. 

Dog-skin. 

Dyed-leather. 

B nibossed-leather. 



Enamelled-leather. 

Fair-leather. 

Flint-leather. 

Glove-leather. 

Goat-skin. 

Grain-leather. 

Green-hides. 

Harness-leather. 

Hides. 

Hog-skin. 

Hungarian-leather. 

Juncten. 

Kangaroo-leather. 

Kid. 

Kip. 

Luce-leather. 

Lamb-skin. 

Legging-leather. 

Lime-leather. 

Linings, 

Morocco-leather. 

Maroquin. 

Oil-leather. 

Pad-leather. 



72 



THE MANUFACTURE OF LEATHEE. 



ParcTiment. 

Patent-leather. 

Eein-leather. 

Eaw-hides. 

Roan. 

Rough-tanned-leather. 

Rasset-leather. 

Russia-leather. 

Saddle-leather. 

Saffian. 

Salted-hides. 

Seal- skin. 

Shagreen. 

Sheep-skin. 

Shoe and Boot-leather. 

Sides. 

Skins. 



Skirting. 

Skivers. 

Sole-leather. 

Split-leather. 

Stamped-leather. 

Striped-leather. 

Sweat-leather. 

Tawed-leather. 

Toppings. 

Trunk-leather. 

Upper-leather. 

Varnished-leather. 

Wash-leather. 

Waxed-leather. 

Welt-leather. 

Whang. 

White- leather. 



Artificial leather is produced by various processes. According 
to the Bonneville method it is made from leather cuttings, shav- 
ings and parings, by reducing while in a dry state to powder, 
which is then mixed with a solution of India-rubber, with or 
without a solution of gum-lac, or of marine glue, to a suitable 
consistency. 

When partially dried, which process is effected by straining 
on wire cloth, or perforated metal, the sheets or slabs of artificial 
leather are pressed between rollers, and, if required, are orna- 
mented with any suitable designs. 

This kind of leather is now largely employed for covering 
cheap and medium-priced trunks, the squares, diamonds, circles 
and other ornamentation being impressed upon it in the manner 
which has been mentioned- 

Artificial leather is also made for soles and heels of shoddy 
shoes by pasting thin skivings together and passing them be- 
tween rollers. 

Messrs. Spill & Co., of Stepney, in 1860, matured the manu- 
facture of a substance which they termed vegetable leather^ and 
resembled leather-cloth in being an application of caoutchouc 



COMMERCIAL VARIETIES OF LEATHER. 73 

to a woven ground-work or back ; but naphtha also took part in 
its preparation, and it possessed other peculiarities. 

Thej produced it in pieces 50 yards long by IJ yards wide, 
and thereby rendered it applicable to many purposes for which 
hides or skins of real leather would be too small. 

They varied its thickness to any desired degree by changing 
the number of cemented layers, and many qualities of leather 
were imitated in it at one-third the cost. 

The vegetable leather was much used in making carriage and 
horse aprons, soldiers' belfs, buckets, harness, book-covers, and 
other articles, a large number of which are now produced from 
Avhat we call rubber cloth. 

The Evans Artificial Leather Co., of Boston, Mass., are pro- 
ducers of various grades and colors of artificial leather, which 
is employed by boot, shoe, carriage, furniture, pocket-book, 
suspender, glove, jewelry-box, and trunk manufacturers. 

There is not the least room for doubt that in the United States 
the leather industry ranks second in importance only to agri- 
culture, when the amount of capital and the labor employed in 
all its branches are considered. It ranks among the leading 
half dozen human industries in many portions of Europe; but 
it is doubtful if even in England it holds the same relative po- 
sition that it does in our own country. 

In England the iron, cotton, and woollen interests are so very 
large, and on the continent of Europe the average consumption 
of leather among the populations is much less than in the United 
States. 

Among the inhabitants of all other parts of the world be- 
sides the United States and British North America, the British 
islands, eastern and southern Europe and Australia, the produc- 
tion of leather is, comparatively speaking, very small, and that 
which is produced is of an inferior quality. 

The hides and skins exported from the excluded sections 
form a most important item in the stock from which leather is 
made in the countries which have been named, and the value 
of the hides and skins, other than furs imported by this coun- 
try, for the year ending June 30, 1883, was $27,640,030, as is 
shown in Chapter III. 



74 THE MANUFACTURE OF LEATHER. 



CHAPTER III. 

STATISTICS OF THE TANNING INTERESTS IN THE UNITED STATES. 

The number of tanneries in the United States, the capital 
invested, amount of hemlock and oak-bark used, number "of 
hides and skins tanned, and the total value of all products is 
given in the following table, which is based on the year 1880, 
and includes the States and Territories. The State possessing 
the largest number of tanneries being placed first, and the others 
following, according to their relative number of tanneries. 

The table does not include the consumption of cutch, gambler, 
sumach, or other tannins, excepting oak and hemlock barks, 
either vegetable or mineral. The imports of foreign materials 
are shown in the table of imports and exports in this chapter. 

It will be noticed that in the table, the State of Pennsylvania 
is credited with the greatest number of hides tanned, while the 
State of Massachusetts is credited with tanning the largest num- 
ber of skins. The reason for the latter being the enormous 
quantities of goat-skins used in the manufacture of Morocco 
leather, and sheep-skins consumed for linings, bindings, and 
skivers. 



TANNING- INTERESTS IN THE UNITED STATES. 



75 





Estab- 














states and Terri- 


lish- 


Capital. 


Hemlock 


Oak 


Hides. 


Skins. 


Total value 


toi'ies. 


ments. 




bark. 


bark. 






of products. 




■ No. 


Dollars. 


Toas. 


Tons 


Number. 


Number. 


Dollars. 


United States. 


3105 


50,222,054 


1,101,526 


353,245 


11,773,171 


19,936,658 


113,348,336 


Pennsylvania, 


642 


15,608,635 


379,069 


122,550 


2,970.680 


635,280 


27,042,068 


New York, 


386 


11,710,415 


334,048 


6,624 


2,503.855 


4,171,290 


23,652,366 


Ohio, 


302 


2,022,990 


5,775 


42,274 


456,015 


434,732 


4,357,273 


Virginia, 


163 


658,973 


69 


11,661 


125,438 


30,628 


1,011,830 


Tennessee, 


147 


470,075 


15 


15,085 


159,524 


66,909 


1,504,660 


Massachusetts, 


133 


2,712,130 


107,324 


74 


1,625,344 


5,724,897 


13,556,721 


North Carolina, 


133 


183,659 


29 


6,154 


83,661 


20,750 


367,920 


Indiana, 


105 


653,349 


1,856 


18,633 


152,375 


57,602 


1,266,653 


Georgia, 


94 


143,441 




30 


115 


1,561 


4,284 


West Virginia, 


93 


515,855 


'"'33 


16,987 


150,317 


50,713 


1,451,528 


Maine, 


83 


2,459,700 


93,406 


180 


879,160 


2,202,158 


7,100,967 


Alabama, 


82 


86,876 


11 


3,591 


44,308 


15,073 


212,-545 


California, 


77 


1,746,750 


103 


22,066 


254,624 


1,314,215 


3,738,723 


Wisconsin, 


73 


1,697,825 


36,806 


134 


327,524 


239,581 


4,324,433 


Michigan, 


66 


1,081,489 


21,139 


1,20.5 


184,011 


341,793 


2,029,653 


Kentucky, 


63 


1,741,430 




31,107 


211,097 


213,840 


2,511,960 


Maryland, 


63 


802,343 


"'75 


24,733 


137,617 


286,250 


1,468,591 


New Jersey, 


55 


1,810,050 


11,332 


14,675 


369,667 


1,783,647 


6,748,094 


New Hampshire, 


53 


603,450 


34,968 




281,490 


404,341 


2,315,616 


Vermont, 


53 


433,300 


12,264 




125,232 


176.250 


1,084,503 


Illinois, 


34 


2,220,114 


50,762 


"137 


395,030 


1,486,570 


5,402,070 


Mississippi, 


34 


37,690 


22 


1,650 


21,020 


9,225 


106,260 


South Carolina, 


28 


42,675 





1,605 


20,967 


4,705 


73,597 


Texas, 


28 


31,850 





825 


10,920 


9,616 


63,750 


Missouri, 


26 


137,850 


l",639 


3,190 


41,419 


152,313 


435,072 


Oregon, 


16 


36,465 


573 


240 


8,961 


5,916 


65,767 


Utah, 


13 


43,200 


322 


81 


5,046 


4,952 


47,267 


Connecticut, 


11 


50,600 


472 


916 


11,950 


24,625 


146,750 


Iowa, 


10 


14,575 




108 


2,470 


12,025 


43,974 


Louisiana, 


10 


9,300 




270 


3,412 


13,280 


28,470 


Arkansas, 


6 


7,683 




222 


2,450 


330 


12,300 


Minnesota, 


6 


32,450 


1,724 




16,716 


7,046 


111,000 


Rhode Island, 


4 


368,600 


7,375 




106,777 




368,000 


Colorado, 


3 


16,700 






4,100 


15,'ioo 


55,800 


Delaware, 


3 


2,800 




*130 


1,400 


195 


7,000 


Idaho, 


2 


1,850 


"'35 




400 


475 


2,216 


Kansas, 


2 


1,167 


20 


'""70 


980 


150 


7,452 


Washington, 


2 


14,250 


210 




2,400 


900 


27,000 


Dist. Columbia, 


1 


9,500 




'"30 


115 


1,561 


4,284 



From this table, whicli is based on the census of 1880, it 
would appear that the average amount of capital invested in 
each tannery is $16,170, the odd dollars and cents being omitted 
in this calculation, as well as in the three which immediately 
follow. 



76 THE MANUFACTUEE OF LEATHER. 

This average is largely exceeded in some portions of the 
country, the seven States possessing the largest average amount 
of capital invested in each tannery, rank as follows: — 

1. Illinois $65,300 

2. New Jersey .52,090 

3. New York . . 30,340 

4. Maine 29,630 

5. Pennsylvania 24,320 

6. California ... . . . . .22,670 

7. Massachusetts 20,400 

The average annual total value of products in each of the 
tanneries in the United States is $36,500; but this is also largely 
exceeded in the States which have just been mentioned. The 
rank of the seven leading States (in the average total value of 
products) in proportion to the number of tanneries established 
in each State, is as follows : — 

1. Illinois $158,580 

2. New Jersey 104,510 

3. Massachusetts 101,930 

4. Maine . . 85,550 

5. New York . . 61,010 

6. California 48,420 

7. Pennsylvania 42,100 

The business of tanning in this country is profitable (in pro- 
portion to the capital invested) in the leading States, in the 
order in which they will now be named: — - 

1. Massachusetts. 

2. Illinois. 

3. Maine. 

4. California. 

5. New York. 

6. New Jersey. 

7. Pennsylvania. 

The profits should be larger in the State of Massachusetts 
than in any of the others, the business annually done being 
about as 5 to 1 to the capital invested; Illinois, Maine, and Cali- 
fornia about 2| to 1 ; New York and New Jersey being scarcely 
2 to 1; while Pennsylvania does not average more thaii If to 1. 



TANNING INTERESTS IN THE UNITED STATES. 77 

Since the census of 1880, a large number of sole leather tanne- 
ries have been located in Virginia, Tennessee, and other South- 
ern States, some being to supply the home demand for this 
variety of leather, and others are entirely devoted to manufac- 
turing leather for export. 

The imports and exports of leather should be closely inves- 
tigated. 

For the twelve months ending June 30, 1882, our exports of 
leather exceeded our imports by $618,403, and for the twelve 
months ending June 30, 1883, the trade was against us to the 
amount of $1,811,131. Such changes are too sudden. 

There are many places in Europe to which our tanned leather 
could be exported with profit, but which are neglected. Take, 
for example, the exports of the United States to Bremen. 

In 1878 we exported from the United States to Bremen tanned 
leather to the value of $149,604, and in 1879 to the value of 
$234,503, showing a gain of $84,699, which has been increasing 
each year, but not to the extent which is possible. 

The condition of the leather industry of Italy should invite 
the attention of American manufacturers and dealers to what 
could easily be made a profitable market for their products. 

Although the manufacture of leather is carried on in all the 
Italian provinces, the product is by no means equal to the wants 
of the nation, and a large deficiency has annually to be supplied 
from other countries. 

This importation is mainly from France, Great Britain, Ger- 
many, and Austria-Hungary, and more recently, to a limited 
extent, from India. 

Leather from the United States has found its way at times, 
during the past twelve years, into the Italian markets, but in 
small quantities, and has been principally our hemlock-tanned 
sole leather, which was re-shipped from Germany. 

The number of the tanneries in Italy at the close of 1879 
was 1316, divided among sixteen provinces. The tanneries are 
mostly small, but water and steam power are used in many of 
them. 

The following table shows the importation of raw hides and 
leather into Italy, from 1869 to 1879, both years inclusive : — 



I 



78 THE MANUFACTUEE OF LEATHER. 

Raw hides. Leather. 

Qaiutals. Qiiuitals. 

1869 ....;.. 129,103 13,188 

1870 98,876 10,552 

1871 ....... 113,743 11,505 

1872 127,202 11,705 

1873 181,434 11,423 

1874 136,761 12,165 

1875 141,752 13,535 

1876 . . . . , . . 139,262 16,350 

1877 . . 134,987 15,376 

1878 106,621 15,719 

1879 . . . . . . . 126,178 15,733 

Under tlie tariff" of May, 1878, the duty on importation of 
sole leather is $4.82, and calf-skins $5.79 per quintal, which is 
220.46 pounds. 

It was highly desirable that the United States should have 
been largely represented in Germany at the Leather Exhibition, 
which commenced June 15, 1881, and continued for three 
months, at Frankfort-on-the-Main. 

In the staple of leather our own country now rivals like manu- 
factures of even England, Germany, and Austria, and no oppor- 
tunity should be lost to so advertise this fact to all the world. 

On account of the cheapness of hemlock bark and other tan- 
ning materials in this country, as well as of a generally better 
class of hides used in the manufacture of leather, our great 
convenience of position for obtaining the raw materials from 
South America, the superior labor-saving machinery employed 
in tanning, and the low rates for freight to Liverpool, there is 
no reason why our exports of sole and other leathers to Great 
Britain and the Continent should not be at least twice as large 
as they now are. 

The English tanners have raised all kinds of objections to our 
leather, they loudly sound extravagant praises of their home 
products, and let not the slightest opportunity pass to cry down 
ours; they say that all our leathers are only colored, and are 
not tanned, that they will not last one-half as long in wear as 
their home products. When, in fact, oar sole and upper leather 
is of better stock, and Avill wear one-fourth longer than three- 



TANNING- INTERESTS IN THE UNITED STATES. 



79 



fourths of that prodaeed in England, even if we do not lime 
and tan so long. 

The following table shows our imports and exports of hides 
and skins, bark for tanning, cutcli and gambir, tallow, fish oils, 
etc., for the twelve months ending June 30, 1883, as compared 
to the twelve months ending June 30, 1882 : — 

12 months to June 30. 



Imports of hides and skins other than fur 
Exports " 

Iinports in excess of exports 
Imports of leather .... 
Exports : 1883. 

Morocco and other fine $385,825 
Leather, sole and upper 6,038,097 



1SS3. ]SS2. 

$27,640,030 $27,841,126 
1,220,158 1,449,737 



Imports in excess of exports in 1883 
Imports for 12 months to June 30, 1882 

Excess of exports over imports to June 30, 1882 

Imports of bark for tanning 
Exports " " 

Excess of imports over exports 

Imports of cutch and gambir 

Exports of tallow 
Imports " 

Excess of exports over imports 

Exports of whale and other fish oils 
Imports " " " 

Excess of exports over imports 



1882. 
$687,638 
7,059,906 


26,419,872 
8,235,053 

6,423,922 


26,391,389 

7,747,544 


2 . 
e30 


1882 


1,811,131 

343,998 

87,528 

256,470 

997,536 

3,248,749 
3,399 

3,245,350 

115,490 
76,553 


7,029,041 

618,403 

490,588 
97,442 




393,046 
784,232 

2,647,515 

5,522 




2,641,993 

420,730 
103,020 



38,837 



317,710 



At the close of 1880 the number of leather-currying estab- 
lishments in the United States was 2319, the number of sides 
of leather curried was 12,464,299, and the number of skins, 
10,655,606, and the total value of all curried products was 
$71,351,297. 

Nearly one-third in value of the whole currying business of 
this country is done in the State of Massachusetts, which ex- 
ceeds in this line the combined products of New Jerse}^, Penn- 
sylvania, and New York. 



80 



THE MANUFACTUEE OF LEATHER. 



More than nine-tenths of the whole currying business of this 
country is done in the twelve States which will be shortly enu- 
merated : — 

The following table shows the twelve States which have been 
mentioned, the number of establishments in each, the capital 
invested, the number of sides of leather and skins curried, and 
the total value of the products in each State, that having the 
greatest value of products being placed first; and the others 
following in relative importance, the table being based on the 
year 1880. 





Establish- 




Sides of 




Total value of 




ments. 


Capital. 


leather. 


Skins. 


products. 


Massachusetts, 


194 


$4,308,169 


4,951,562 


5,178,609 


23,282,775 


New Jersey, 


56 


1,983,746 


818,804 


1,703,316 


8,727,128 


Pennsylvania, 


455 


2,570,969 


1,272,931 


404,874 


7,852,177 


New York, 


185 


1,720,356 


1,048,581 


639,772 


6,192.002 


Wisconsin, 


61 


1,299,425 


734,800 


582,451 


4.496,729 


Ohio, 


251 


1,089,075 


632,615 


256,054 


3,886,627 


Maine, 


34 


510,900 


518,850 


232,552 


2,612,350 


Illinois, 


18 


537,786 


251,660 


431,920 


2,391,380 


New Hampshire, 


37 


351,850 


435,450 


339,466 


2,161,734 


California, 


63 


427,350 


266,054 


466,450 


2,001,850 


Indiana, 


93. 


381,552 


276,760 


37,lsl 


1,461,776 


Michigan, 


44 


256,311 


161,308 


63,351 


996,932 



EXAMINATION OF LEATHERS. 81 



CHAPTER lY. 

EXAMINATION OF LEATHERS.^ 

The determination of the value and quality of leather by a 
chemieo-technical examination has heretofore been perhaps 
more neglected than that of any other product of industry and 
commerce. The consumer or dealer either does not examine 
the leather at all, but buys his supply from a well-known tan- 
nery, or judges it solely by the cut, flexibility, and weight. 
Although it cannot be denied that an, expert may rely on exter- 
nal marks, it must nevertheless be admitted, that these leave us 
in the dark in man}'- points as regards the value of leather. "We 
need, for instance, refer only to the varying percentage of w^ater 
in the different varieties, according to the time they have been 
stored, to prove the importance of a method of testing based 
upon measure and weight. 

Unfortunately no thorough examinations in this direction 
have thus far been made by competent experts, and the litera- 
ture in regard to this matter found in chemieo-technical works 
is very meagre. Marquis,^ who undertook a chemical examina- 
tion of different varieties of leather, made use of the following 
process: — 

Marquis's Method. 1. Determination of fat and resin. — An 
accurately weighed quantity of leather is cut into small pieces, 
which are thoroughly dried in an exsiccator, and then three 
times in succession digested with ether. After distilling off the 
latter, the matrass, the weight of which has been previously 
determined, is weighed together with the residue it contains. 

1 Bolley's Technologie, 35 (Bd. vi. 4). 

2 Pharmac. Zeitschr. fiir Russland, Jalirg. 4, Heft 10, S. 389 ; cf. Zeitschr. 
fur analyt. Cliemie, 1866, S. 236. 

6 



82 THE MANUFACTUEE OF LEATHEE. 

The mixture, consisting of fat and resinous substances, is treated 
with cold alcohol to separate the resinous constituents from the 
fat. This method of determining the fat cannot be an accurate 
one, since, besides fat, other substances, for instance tannic acid, 
are dissolved by the ether. 

2. Determination of lime in leather. — 6.211 grammes of 
shredded leather are burned to ashes in a platinum crucible, 
the ash is treated with hydrochloric acid, the solution fil- 
tered, and the filtrate sufficiently washed out with water. The 
lime is precipitated from the filtrate with ammonium hydrate 
and ammonium oxalate. The precipitate is washed and dis- 
solved in nitric acid. The oxalic acid in the solution thus ob- 
tained is determined by solution of potassium mangauate, and 
the lime calculated from the quantity of potassium manganate 
used. 

Marquis found between 1 and 3 per cent, of lime in the dif- 
ferent samples. 

3. Determination of the Tanning Constituents. — Heinzerling 
proposes the following method: — 

Determination of Water. — 10 grammes of sole or upper leather 
in the form of small cubes are dried in a dry current of air at 
170° to 190° F. until a decrease in weight is no longer observed. 

It is best to use for this purpose such an air-bath as is shown 
in Fig. 1. The cubes of leather, contained in a tube expanding 
in the centre and running to a point in front, are placed in the 
air-bath and dried. 

Percentage of Ash. — 5 grms. of leather are heated in a porce- 
lain or platinum crucible until all coal is burned. Should this be 
difficult to effect, some ammonium nitrate is carefnlly added in 
order to accelerate the process. The ash is weighed and calcu- 
lated in the usual manner. 

In case the percentage of ash is very high (7 to 10 per cent.), 
so as to arouse the suspicion of the leather having been made 
heavy with inorganic substances, the ash is qualitatively tested 
by the ordinary analytical process and the admixtures, such as 
chlorides of barium or calcium, which may be found, determined 
in freshly weighed leather. 

As lime in leather exerts an injurious influence upon its 



EXAMINATION OF LEATHER. 



83 



durability, causing, especially, brittleness in upper leather, it is of 
the utmost importance to learn the percentage of that substance. 
For this purpose the residue obtained from a determined quan- 
tity of leather is dissolved in hydrochloric acid, the solution 



Fisf. 1. 




diluted with distilled water and filtered. The filtrate is boiled 
with a few drops of nitric acid and compounded with solution 
of ammonium hydrate and sal-ammoniac to separate the iron 
and alumina. The lime is precipitated as calcium oxalate with 
ammonium oxalate, and weighed as calcium carbonate or caus- 
tic lime. Members of the fifth group represented in the hydro- 
chloric solution of ash must of course be previously removed. 

Percentage of Fat. — As many varieties of leather are exces- 
sively greased with fat, in order to increase the weight, it is of 
interest to determine the percentage of fat. For this purpose 5 
to 10 grms. of shredded leather are, according to Caillelet, placed 
in a small matrass and boiled in a 6 to 8 per cent, solution of 
soda or potash lye for some time, in order to saponify all animal 
and vegetable fats. By compounding the soap solution with 
hydrochloric acid, the free sebacic acids are separated upon the 
surface of the fluid. 



84 THE MANDFACTUEE OF LEATHER. 

To determine the sebacic acids, they are dissolved in 20 or 
30 cubic centimeters of oil of turpentine. The fluid, together 
with the fat solution, is placed in a graduated tube and by reading 
the volume of the layer of oil of turpentine containing the sebacic 
acids in solution, the quantity of the latter is obtained from the 
increase in volume of the oil of turpentine. If, for instance, 
20 c.c. of oil of turpentine have been used and the volume of 
the solution of oil of turpentine and sebacic acid amounts to 26 
c.c. the amount of sebacic acids will, by subtraction, be found 
to be 6 c.c. The weight of the sebacic acids is obtained by 
multiplying the cubic centimeters found with the specific 
gravity. 

These methods of determining the fat, although not entirely 
accurate, are sufficiently so for technical purposes. 

Determination of Nitrogen. — As the cleansed leather skin 
shows a considerable percentage of nitrogen, Miintz has pro- 
posed to determine the percentage of nitrogen in leather, in 
order to draw from it a conclusion in regard to the chemical 
composition of leather. The method is available for tan-leather 
as well as mineral-leather. 

0.6 to 1 grm. of leather rasped or finely shredded is mixed 
with a large quantity of soda-lime and placed in a tube of con- 
siderable length and the nitrogen determined as ammonium 
according to the Barrentrapp- Will method. . As the bubbles 
of ammonium of a larger molecular weight form also combina- 
tions with platinum chlorine, to avoid errors, the platoso-am- 
monium chloride obtained by precipitation with platinum chloride 
must not be weighed as such and the nitrogen calculated from 
it, but the precipitate should be heated in a porcelain crucible 
and the percentage of nitrogen calculated from the metallic 
platinum obtained (1 equivalent of platinum = 1 equivalent of 
nitrogen). 

Coriin, a small quantity of which occurs in the skin, has ac- 
cording to Reimer^ the formula Cj^H^gNj^Oij containing con- 
sequently 28.3 per cent, of nitrogen. The membranous 
tissue of which the raw skin chiefly consists, has the 
formula C,jH^NjOg and contains 30.3 per cent, of nitrogen. 
Suppose .the .skin contains 4 to 6 per cent, of coriin, the 



EXAMINATION OF LEATHER, 85 

quantity of nitrogen may be taken in round numbers as 
amounting to 30 per cent. If, therefore, an analysis should show 
15 per cent, of nitrogen in a variety of leather, the latter con- 
tains 50 per cent, of skin substance and 50 per cent, of other 
substances such as water, tanning materials, fats, etc. 

Tanning Substance. 1. Tannic Acid. — A knowledge of the 
quantity of tanning material contained in a variety of leather is 
of more scientific than practical interest. An accurately tested 
method of establishing the quantity of tannic acid in tan-leather 
is riot yet known. Marquis's method, as already mentioned, 
has many defects. Other methods require a separation of the 
tannic acid from the animal fibre, which can scarcely be effected 
without decomposition of the latter. Mittenzweig's method is 
the only one worthy of a thorough test. 

2. Mineral Constituents. — The tanning materials in mineral 
tanned leather, ferric salt in Knapp's process, and alkaline 
chromates, chromium salts and aluminium combinations in 
Heinzerling's, can be readily determined, after destruction of 
the fibre tissue, by the usual analytical process. 

The cutting surface is generally taken as a criterion by which 
to judge whether leather is thoroughly tanned. It should be 
uniform throughout the entire mass and show no dark stripes 
on the sides nor in the centre. The cutting surface of leather 
not thoroughly • tanned presents an unequal appearance, dark 
stripes occurring on the side as well as in the centre. 

The behavior of tan-leather towards boiling water has also 
been made use of to determine whether the leather has been 
thoroughly tanned. By heating in water to the boiling point 
a thin piece of leather not sufficiently tanned, it swells up 
considerably, and becomes transparent and tough like pig 
skin, only the thoroughly tanned places remaining opaque and 
of a coffee-brown color. Such leather, when rubbed between 
the fingers, is soft and sticky. The decoction obtained from 
leather insufficiently tanned is generally already turbid on 
cooling, has a yellow to pale-brown color, and on evaporating 
the fluid after cooling some gelatine remains behind. Thin 
strips of thoroughly tanned leather, when boiled in water, 



86 THE MANUFACTURE OF LEATHER. 

shrink considerably, become opaque and of a coffee-brown color, 
and brittle when rubbed between the fingers after cooling. 

The decoction obtained from thoroughly tanned leather is 
transparent and of a reddish -brown color and, when evaporated 
to the consistency of sj^rup, shows no sign of gelatinizing. 

Determination of Means used to Increase the Weight of 
Leather. — It is frequently the case in modern times, especially 
in Germany and Great Britain where tanning material is high 
that, in order to obtain greater weight, a concentrated solution 
of banum chloride, aluminium chloride or grape-sugar isNnot 
only applied to the flesh side of tanned sole and upper leather, 
but the entire product is sometimes saturated with it. The 
detection of these adulterations of leather is not very difficult. 
Digest the leather in lukewarm water for a few hours, acidulate 
a part of the resulting aqueous solution with nitric acid and 
test it with nitrate of silver for chloride, and another part of the 
solution with sulphuric acid for barium salt. Ammonium 
hydrate is used as a reagent for aluminium salts. 

Precipitates are formed when any of these substances are pre- 
sent. The chloride of silver soon darkens on exposure to light, 
while the precipitate of alumina produced with ammonium is 
very voluminous. If only a small degree of turbidity occurs 
during these reactions, no adulteration has taken place. The de- 
tection of grape-sugar is somewhat more difficult, as the tanning 
material, for instance tannin, passing into solution yields, on 
splitting, grape-sugar, which must be taken into consideration. 
The leather is digested in lukewarm water for some time and, 
in order to precipitate all the tannic acid contained in the solu- 
tion, some cupric acetate is carefully added. The solution is 
then filtered and when a precipitate is formed, some Fehling's 
copper solution is added, and the whole boiled for twelve to fif- 
teen minutes. A strong separation of cuprous oxide is a proof of 
the leather having been weighted with grape-sugar. 

Physical Methods of Testing Leather. 

If it is only desired to test the quality of leather, this can be 
directly ascertained by the following methods: — 



EXAMIN"ATION" OF LEATHER. 87 

I, Change in Volume and Ability for resisting Water: — As the 
ability for resisting water may be considered one of the principal 
properties of leather, the variety which absorbs water the most 
slowly and in the least quantity, must evidently be considered 
as possessing qualities which should testify highly in its favor. 

The following table, on page 88, can be understood without 
further explanation. It was compiled by Dr. Heinzerling, and 
has been admitted into the present work in order to invite atten- 
tion to his manner of tanning or rather tawing ; hoping that it 
may eventually be perfected by some of our American inventors 
into a generally acceptable process, and that whatever objection 
there may now be to the leather thus economically produced 
may in the course of time be overcome. The manner of tanning 
leather by this process will be considered in a subsequent 
chapter. 






THE MAISTTFACTURE OF LEATHER. 



.Sf a 



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EXAMINATION OF LEATHER. 89 

The figures in the table on page 88 show that sole leather 
tanned in the usual manner absorbs water with the greatest 
facility, while Heinzerling's leather absorbs none at first, in 
sixteen hours only 6| per cent, of its weight, and in four days 
only 20 per cent. 

The tan leather became considerably lixiviated so that the 
water assumed a dark color, and the sample A did not increase 
in weight after sixteen hours, while B actually decreased some- 
what in weight from the first to the second day. In bending 
the tan leather after immersion for thirty-five minutes, the 
water oozed out in drops, while Heinzerling's leather did not 
show this phenomenon even after four days' immersion, drops 
of water oozing finally only from the upper leather. 

II. Testing the Strength of Leather. — The strength of leather 
can be tested in two directions by determining either its power 
of resisting tearing or that of breaking. The ability to resist 
tearing must be especially taken into consideration in varieties 
of leather intended for machine belts and main braces, while 
the power of resisting breaking when frequently bent in the 
same place deserves special attention in leather to be used as 
upper and sole leather. 

Special apparatuses have been constructed to determine the 
power of resistance against breaking. We will here briefly 
describe Wiener's apparatus, Fig. 2. 

The samples of leather to be tested are best cut with a punch 
from a determined portion of the side. They receive either 
the shape of A, or, what is of great importance, if the stretch- 
ing and remaining elasticity is to be tested at the same time, 
the shape of Y. In making comparative tests care should be 
had to use samples of equal thickness. The piece of leather A 
is stretched in the two clamps K and k. The clamp k is con- 
nected with the lever h by means of the drawing-rod z, which 
passes through a corresponding aperture in the support T. 
The long arm of the lever on which hangs the balance s, is to 
the shorter in the proportion of 100 to 1. In an unweighted 
state both arms of the lever are in equilibrium. The entire 
apparatus is fastened to a strong wooden frame. The support 
B, which is screwed to T, prevents the levers from turning over 



90 



THE MANUFACTUEE OF LEATHEE. 



at the moment A tears. The scale-basin s is weighted until 
the leather tears. The more the leather stretches before tearinsf 

Fis. 2. 




and the greater the weight required for tearing, the greater the 
strength it possesses. The power required for tearing is 
obtained by multiplying the weight used by 100. 



Fisr. 3. 




no^—f320 



i3zo—/5*3 rsn-irs-h llf. 



No special apparatus has thus far been constructed to 
test the resistance of leather to breaking, the reason being 
probably that the task is a very difficult one. Experienced 



EXAMINATION OF LEATHER. 



91 



technologists have made use of the following method : Differ- 
ent pieces of leather are fastened to the edge of the flj wheel 
in such a manner that they are bent to and fro at every revo- 
lution of the wheel. A conclusion as to the power of resistance 
to breaking is drawn by observing the behavior of the separate 
pieces up to the moment of breaking, the velocity of revolution 
being at the same time taken into consideration. 

To obtain comparative results care must be had that the 
pieces to be tested are fastened to the fly wheel in such a man- 
ner that the angle of bending is the same for all pieces. 

We here give an interesting table by A. Schwarz & Co./ 
showing the strength of the skin in different places. 







1 


2 


3 


4 


5 


6 


7 




P 


P 


P 


P 


P 


P 


P 


r 


1058 


1102 


1296 


1417 


1177 


926 


1102 




893 


1069 


1289 


1362 


1234 


1036 


937 


A... ^ 


882 


893 


1302 


1302 


1234 


1102 


1190 






992 


959 


1113 


1212 


1201 


1080 


1147 




. 


860 


959 


981 


1080 


1212 


1102 


981 




1069 


1025 


1373 


1362 


1190 


1147 


992 




904 


992 


1102 


1362 


1256 


970 


827 


B ... ] 


992 


1047 


1472 


158S 


1256 


1069 


760 




904 


1102 


1417 


1544 


1234 


1135 


838 




948 


1168 


1373 


1478 


1135 


lObO 


827 




959 


937 


1433 


1450 


1214 


937 


771 




970 


1168 


1538 


1533 


1517 


1147 


771 


C ... ] 


1036 


1190 


1373 


1577 


1373 


970 


727 




1147 


1256 


1494 


. 1599 


1192 


1235 


793 




1312 


1278 


1433 


1417 


1467 


1036 


804 




1224 


1157 


1450 


1522 


1438 


1168 


992 




1406 


1245 


1509 


1588 


1433 


1135 


915 


D... \ 


1433 


1450 


1433 


1544 


1356 


992 


1047 




1323 


1340 


1566 


1433 


1323 


1003 


937 




1516 


1406 


1461 


1455 


1268 


1036 


992 




937 


1080 


1279 


1389 


1279 


1036 


948 




882 


1202 


1246 


1318 


1268 


1025 


1004 


E ... ■{ 


772 


1245 


1323 


1406 


1467 


1125 


992 




662 


1212 


1268 


1461 


1301 


1012 


1125 




618 


1069 


1362 


1698 


1698 


1307 


838 



' Verhandlungen des Vereins zur Beforderuiig des Gewerbefleisses in Preus- 
sen. 



92 THE MANUFACTURE OF LEATHER. 

The grain portion of half of a side of leather, 57 inches long 
and 25 inches wide, is divided lengthwise, as shown in Fig. 3, 
into seven fields, and the width into 25 fields, so that 175 strips 
each 8^ inches long and 1 inch wide, are obtained. 

In the table the breaking weight P is given in pounds. 

In Fig. 3, the results of the table are represented by light 
and dark shading of the separate fields. On examination it 
will be found that there is a considerable difference in the tear- 
ing strength of the various places even in the grain piece, the 
middle portion being the strongest, the part towards the hfead 
and tail becoming weaker and weaker.^ 

^ A belt out lengtliwise from a side of leather will therefore be weaker on both 
ends than in the centre. 



PART II. 



CHAPTEE Y. 

ANIMAL SKIN. 

In tbe production of leather there are two classes of raw pro- 
ducts with which the tanner has to deal, they are — 

1. Hides and skins to be converted into leather, and 

2. Materials by the aid of which the changing or tanning 

is effected. 

Of the varieties of hides and skins that are employed for tan- 
ning purposes and the kinds of leather which they yield we 
have treated in the opening chapters ot this work. Of the 
materials used for tanning we shall hereafter treat in Chapters 
VI. and YII. The object of the present chapter being to ex- 
plain the structure of the skin and its behavior with reagents, 
without which knowledge an intelligent prosecution of the 
art of tanning is rendered difficult and at times hazardous. 

Animal skin is constructed with several readily distinguish- 
able layers which behave differently in a chemical as v/eil as 
in a physical respect. 

The upper part of the skin in which the coat of hair, wooi or 
fur is rooted, is termed the epidermis or cuticle, next beneath 
this is the corium or leather-skin, and placed next to this is the 
under-skin. 

The epidermis is composed of two layers : — 

1. A tissue analogous to the corneous matter of the hoofs, 
horns, nails, and hair, and is composed of layers of pavement 
epithelium cells, which when first formed are spherical, gradu- 
ally becoming dry and flattened ; the deeper layers being more 
distinctly cellular, while the outer one is scale-like, and. 



94 THE MAlSrUFACTURE OF LEATHER. 

2. An inferior or basement layer, Malpighi's net [rete Malpi- 
ghianum\ which consists of a layer of cells charged with fluid, 
and serves to feed or renew the horny tissue, being in its turn 
supplemented by vessels situated in the corium. 

The epidermis does not combine with tannin or other sub- 
stances by the agency of which leather is produced. Hence it 
becomes useless to the tanner, and therefore the first process 
to which hides and skins are subjected by him is that for re- 
moving the hair and epidermis, and the portion of the skin 
thereby exposed is technically termed the " grain side." 

The corium or leather skin is divided into an intermediate 
layer next to the epidermis and is the actual leather skin. 

Both are made up of interlaced bundles of connective tissue 
fibres, placed crosswise above each other, and running parallel 
with the surface of the skin ; but being more or less filled with 
fluid matter that serves to renew the cuticle and maintain the 
skin in a pliant and moist condition. On treating the skin with 
water these matters are removed, and ultimately there remains 
but the fibrous portion saturated with water. In this state it 
appears semi-transparent, and if the water be expelled by a gentle 
heat, it assumes the physical appearance of horn, constituting 
only about 32| to 33 per cent, of the raw hide. 

The quality of the leather which can be produced from a skin 
depends upon the thickness, flexibility, and strength of the 
corium, which exceeds the combined thickness of all the other 
layers forming the remainder of the skin. 

A peculiar albuminoid substance (coriin) is stored between 
the separate fibres of the corium, which substance in a dry 
state, connects and cements together the raw skin fibres. 

The under-skin consists of a loose connective tissue, in which 
the sweat and fat glands, the blood-vessels and muscular fibres 
are embedded. It is previously removed in the " beam house" 
of the tannery and takes no part in the tanning process. 
. The side upon which the connective tissue of the under skin 
is located is technically designated 'as the " flesh side." 

Fig. -i shows an enlarged transverse section of the skin. 

D is the connective tissue of the under-skin showing the 
sweat glands (/, with the ducts A, through which this secretion 



ANIMAL SKIN. 



95 



passes out to the surface of the skin ; 5, is the Malpighi net, and 
c? the corium; c, papillse of the skin ; e, /, lobules of adipose 
tissue; ^, the external orifices of the sweat or perspiratory glands; 
k. hair follicle ; m, hair papilla ; ti, hair bulb ; o, shaft of 
hair in hair follicle ; p^ openings of the sebaceous glands. 



Fis 







The horny layer of the epidermis, «, shows on different 
places, as at /, such structures as hair, wool, bristles, etc., 
which, as seen in the illustration, are not embedded immediately 
in the surface, but in capsules or shafts, called " hair sacs^^ or 
^^ hair roots,^^ reaching from the epidermis to the actual corium. 
In these sac-like depressions the hair is fastened by means of 
" hair hulbsT The hair is coated with a protective layer of fat 
by small fat glands, the follicles of which enter the upper part 
of the hair-sac. 

Malpighi's rete raucosum accompanies the bottom of the hair 
sac, the walls of the latter consisting of flat epithelial cells, 
which develop, only in another form, the hair itself. 

The horny shaft of the hair is a section projecting above the 



96 THE MANUFACTUEE OF LEATHER. 

skin, and when completely developed is provided with a minute 
epithelium, forming the upper skin of the hair. 

In boiling with water the connective tissue fibres are con- 
verted into glue, the other constituents taking no part in the 
glue formation. The chemical process taking place during the 
latter operation is not yet thoroughly understood. The relations 
of the glue-yielding tissues to the glue, seem to be similar to 
those existing between starch and paste. Starch, as well as the 
glue-yielding tissues, is a body of an equally pronounced nature, 
both being insoluble in cold water and remaining unaltered 
within certain limits. By boiling with water, they entirely 
lose their organized structure and form a solution, which on 
cooling separates, in glue, a colorless jelly, and in starch a body 
very similar to glue. 

The skin, when slowly and completely dried in the air and 
stored in a dry place, can be kept for along time. When dried 
by exposure to strong sun heat, it undergoes an alteration hav- 
ing an injurious effect. The fibres of such skin, after complete 
softening by soaking, which can onl}^ be accomplished with 
great difficulty, show very little strength. This excessive effect 
of heat may even cause the skin fibres to dissolve, in soaking, 
into a glue-like jelly, as has, for instance, been frequently ob- 
served in buffalo skins carelessly dried by exposure to strong 
sun heat. 

Moist skins left to themselves decompose in a short time with 
the usual products of putrefaction making their appearance. 

Covered with salt or immersed in strong brine, skins can be 
kept for a long time. 

The chemical and morphological constitution as far as inter- 
esting to us, may be briefly given as follows: — 

" The connective tissue fibres or fibrillee form the morpho- 
logical structure of the skin tissue, the intercellular substance 
or coriin, as has been conclusively shown by Eollet,^ and later 
b}'' Eeimer,^ Ijii^g between them. 

' Wiener Akademieberichte 30, 37, 39, 308, and Dingl. Polyt. Journal 149, 
298. 

2 Dingier, Polyt. Journal, 143, 205. 



ANIMAL SKIN". 97 

The intercellular substance is an albuminous body soluble, ac- 
cording to Eollet and E,eimer, in lime and baryta-water, and 
also, according to Reimer, in a 10 per cent, solution of common 
salt, while in one of greater or less concentration it remains in- 
soluble. This behavior towards solutions of common salt and 
lime-water can therefore be used for separating it. 

To prepare coriin the skin is washed with water until all the 
soluble albuminoid substances are extracted. The skin is then 
placed in saturated lime-water six to eight days, which dissolves 
all the coriin. The fluid is then filtered and dilute acetic or hy- 
drochloric acid added until the appearance of a slight acid reac- 
tion. The coriin is separated as a flaky precipitate which, by 
standing quietly, settles on the bottom. 

To obtain the coriin perfectly pure and free from an admix- 
ture of cell elements, it isredissolved in lime-water, filtered, and 
again precipitated with acids. Coriin precipitated from alka- 
line or common salt solution is constant in all respects; on de- 
taching it from the filter gray or gray-white lamina are formed 
which on exposure to the air assume a somewhat darker color. 
On shaking up with water, it swells up without actually dis- 
solving, and is converted into a paste-like mass. By diluting 
the latter with water an opalizing fluid is obtained which by 
standing forms a precipitate, nothing whatever remaining in 
solution. The addition of a small quantity of common salt in- 
creases the swelling capacity, while that of a larger quantitv 
promotes solution, and that of a saturated solution of common 
salt effects precipitation. By adding spirit of wine to the sub- 
stance dissolved or swelled in w^ater, a flaky precipitate is sepa- 
rated. 

After removing the spirit of wine the flakes act in the same 
manner as before. Although a separation is also eflected by 
ether, the precipita,te by remaining in contact with the ether 
for some time, can only be swelled with difficulty. Most of the 
alkaline salts and alkaline earths have, like common salt, a dis- 
solving and swelling effect upon coriin, small quantities of them 
increasing its solubility in water, which is a very important fact 
deserving special attention in tanning. 

Most natural waters, as is well known, contain small quanti- 
7 



.98 THE MANUFACTURE OF LEATHER. 

ties of alkaline salts and earths. In using such water for 
swelling, cleansing, and washing the hides, the swelling influ- 
ence which these salts have upon the coriin must be taken into 
consideration. 

In hard water containing much of these salts, the skins must 
remain for a shorter time than in soft water, ^. e., such as con- 
tains but a small quantit}'- of salts or none whatever. 

In speaking of the use of water in the tannery, we will con- 
sider this point more closely. 

Since by repeated treating with lime or baryta water, fr^sh 
quantities of soluble substances can be constantly withdrawn 
from the skin, it is not improbable that the intercellular sub- 
stance is a decomposing product of the connective tissue sub- 
stance. This circumstance deserves consideration in depilating 
the skins and hides with lime, for if the latter remain too long 
in the lime, a part of the connective tissue is converted into 
soluble substance which is lost in the succeeding cleansing of 
the hides. 

Liming continued too long gives poor weight, and besides the 
leather prepared from skins too long limed is not strong. 

Coriin is insoluble in acetic acid, and only partly soluble in 
dilute hydrochloric acid, the undissolved portion settling after 
long standing, as a flaky precipitate. 

Coriin is readily soluble in pure alkalies and solutions of 
alkaline earths. 

Potassium ferro and ferridcyanide produce no precipitation 
in acidulated or neutral solution, but effect precipitation when 
acting upon strongly swelled coriin. 

Ferric chloride, cupric sulphate, cupric chloride, and sugar of 
lead form no precipitate in neutral or slightly alkaline solutions, 
while it is produced by basic acetate of lead, excess of tannic 
acid or basic acetate of iron. 

Coriin is free from sulphur, since on melting the substance 
with potassium hydrate, no potassium sulphide remains behind. 

From the composition found by the elementary analysis, 
Keimer derives the empirical formula CjoHjoNjqOjj. 

The connective tissue substance^ differs in many respects 

1 Muspratt, Technische Cliemie, Bd. III. 91. 



ANIMAL SKIN", 99 

from the intercellular substance, but principally by being in- 
soluble in lime-water which, as we have seen, readily dissolves 
cori'in. It is dissolved by acetic, hydrochloric, and other 
acids, but separates again on neutralization. 

To prepare connective-tissue substance, place cleansed skin in 
acetic acid for some time. The skin swells up more and more, 
while the acetic acid dissolves a portion of the connective-tissue 
substance. The fluid which becomes of a slimy nature separates 
on being diluted with water, filtered, and neutralized, and be- 
comes a flaky precipitate. To obtain the substance in a pure 
state, the obtained precipitate is washed with lime-water in 
order to remove coriin which may be present, and is again dis- 
solved in acetic acid. Some potassium is added to the solution 
until only a very slight acid reaction is perceptible. The fluid 
is then saturated with common salt, the precipitate, after stand- 
ing quietly, collecting upon the surface. It is readily filtered, 
and first washed with slightly acidulated water and then with 
pure water, and finally dephlegmated with alcohol. 

Pure connective-tissue substance swells up when placed in 
water, and reassumes its original softness. 

Acetic acid, as mentioned previously, dissolves connective- 
tissue substance, the solution containing the substance but not 
dissolved as glue. Potassium ferro and ferridcyanide produce 
precipitates in the solution. 

By boiling with water the pure substance is readily con- 
verted into glue. 

Pure lime-water does not dissolve it; an essential difference 
from coriin. 

Tannic acid, basic acetate of lead, and basic sulphate of iron 
produce precipitates. 

The empirical formula CuHojlSTjOg is derived from the ele- 
mentary analysis. 

This being the same composition as that found by Cramer for 
the fibroin of silk, Eeirner designates the matter extracted by 
acids from the skin as skin fibroin. 

The empirical formulse calculated for coriin and skin fibroin 
give us no information about the relation or close analogy of 



100 THE MANUFACTURE OF LEATHER, 

the two bodies to each other, their chemical constitution being 
still unknown. 

The most important property of the skin fibre, which 
deserves special attention from a practical standpoint, is that it 
swells up strongly in one-half per cent, solutions of inorganic 
acidS; and is entirely dissolved in somewhat concentrated acids 
if subjected sufficiently long to their action. 

The swelling influence exerted by acids upon the skin fibres 
is, as is well known, used on the one hand to make the skin more 
sensitive for the reception of the tanning material, and, on the 
other, to effect the isolation of the compound bundles of 
connective-tissue fibres into separate fibres, increasing the 
surface thereby at the same time. It is self-evident that by 
carrying this swelling process too far, the strength of the fibre 
suffers injury. 

Later on, in speaking of the preparation of the hides and 
skins for tanning, we shall discuss this point more fvilly. 



CHAPTEE VI. 

YEGETABLE TANNING MATERIALS. 

Section I. Tannin or Tannic Acid. 

In considering tanning materials we shall first discuss tannin 
or tannic acid and the methods for its preparation, and then 
mention the vegetable substances containing tannin and the 
quality of leather which each produces, and the power of 
absorbing and retaining different tannins by the skin ; after 
which we shall mention the mineral substances employed as 
tannins, and finally name the artificially prepared tanning sub- 
stances. 

Tannin or Tannic Acid. — Tannic acid and vegetable substances 
containing it are still of the greatest importance to the tanner. 

The number of plant substances in which tannic acid occurs 



VEGETABLE TAISTNING MATERIALS. 101 

is very large, many plants containing it in all parts, others only 
in the roots, leaves, blossoms, sap, fruits, or excrescences. 

Though these substances may differ very much as regards 
their origin and properities, they resemble each other in con- 
taining a material capable of converting hide into leather, and 
having the further characteristics of possessing acid properties 
and an astringent taste, and producing a green or blue precipi- 
tate in ferric salt solutions. 

These different principles were at first considered as identical 
with the tannin of the gall-nut or gallotannic acid. A deeper 
consideration has allowed us to separate them into several 
varieties, the leading of which are: The tannin of the ordinary 
gall-nut and of the galls of China and Turkey, or gallotannic 
acid ; the tannin of the coffee, or coffee-tannic acid ; the tannin of 
the cashew, or cashew-tannic acid ; the tannin of the yellow 
wood, or morintannic acid ; the tannin of the quercitron, or 
quercitannic acid; the tannin of the cinchona, or quinotannic 
acid. 

The chemical and physical behavior of each of these tannins 
varies according to its origin. The tannins were formerly 
divided according to the color of the precipitates obtained with 
ferric salts, into such as precipitated the latter " blue-black," and 
into tannins precipitating ferric salts " green." 

The tannins which precipitate the ferric salts blue are met 
with in the gall-nut in the leaves and bark of the oak, of the 
poplar, of the pear tree, of the hazel tree, the leaves of the 
Arhutus uva ursi, of the Arbutus uveda, of the Lythrue sali- 
caria, etc. The tannins which precipitate the ferric salts green 
are found in the cashew, the cinchona, the pines, the roots 
of the Crameria ariandra^ of the Rheum rkaponticum^ of the 
Potentilla tormentilla^ the bark of the Salic ariandia and undu- 
lata^ of the Alvus ylutinosa^ of the Pinus larix^ of the Phizophora 
mangle^ etc. 

But the distinction above named is not broad enough, since 
extract of gall-nuts, which would precipitate ferric salts black, 
colors them green when mixed with tartaric or acetic acid, and, 
on the other hand, tannin, which by itself colors ferric oxide 



102 THE MANUFACTURE OF LEATHER. 

green, gives, in the presence of a very small quantity of alkali, 
a blue color to the precipitate. 

It may* therefore be supposed that the difference in the 
behavior towards ferric salts may, in certain cases, be traced to 
the presence of acids or alkalis in the tannin solutions, 

R. Wagner' applied the term 'physiological tannic acids to 
such as are adapted to the formation of leather and precipitate 
ferric salts black, and that oi pathological tannic acids to those 
not suitable for tanning. 

The first are found in the vegetable normal tissues, the 
second in the pathological productions due to the puncture of 
insects. The precipitates formed by the latter with gelatine, it 
is claimed, would not be safe from putrefaction.^ 

Pathological tannic acid is claimed to be contained in the 
barks of the oak, pine, beach, and willow, in bablah (shells and 
fruits of Acacia bamhola), in valonia (Amata valonia\ hulls of 
dividivi [Catsalpinia coriaria), sumaG {Wius coriaria\ and myro- 
balans (fruit of Terminalia chehula). 

These tannic acids yield, when fermented or subjected to the 
action of dilute mineral acids, no gallic acid, and when distilled 
dry, no pyrogallol. With ferric salt they give blue-black pre- 
cipitates. 

Pathological tannic acid is claimed to be contained in gall- 
nuts, catechu, etc. It precipitates glue solutions completely, 
but is said to give leather of no technical value. 

Gallic acid is formed by fermentation or splitting with acids, 
and pyrogallol by heating. Wagner's assertion that leather of 
technical value is only obtained with the assistance of tannins 
designated by him as physiological ones, cannot be accepted as 
correct, since tanning materials containing only so-called patho- 
logical tannin are largely used in modern times either by them- 
selves or mixed with others, and yield satisfactory results. 

Our knowledge of the different tannic acids is yet very 
incomplete, only that contained in gall-nuts having been 
thoroughly examined. The principal obstacle to a closer de- 

1 Zeitsclir. f. analyt. Chemie, 1866, 1. 
» Bulletin de la Soc. Chim., 1866, ii. 461. 



VEGETABLE TANNING MATERIALS. 103. 

termination of the nature of tannic acids is found in the fact 
that all tannic acids form amorphous substances which cannot 
be crystallized, their insolation being consequently very difficult. 
Besides they are very changeable and decomposable bodies, 
which are frequently converted into other combinations while in 
the hands of the chemist. 

Oallotannic Acid. — Tannin of the gall-nut. This is, as has 
been stated, the best known of all the varieties of tannin. 
Discovered by Lewis in the eighteenth century, gallotannic 
acid was particularly studied by Pelouze, who perfected a pro- 
cess first broached by Lambert for its extraction, which is yet 
followed, with the difference only of a few details. 

This process is based on the following principles r Of all the 
matters contained in the gall-nut, tannin has the greatest solu- 
bility in water. Dry tannin is insoluble in anhydrous ether, 
but in presence of a small quantity of water a solution of tan- 
nin is formed in the aqueous ether; this syrupy solution is not 
mixable with ether, but it dissolves in alcohol ; mixed with 
water, this solution of aqueous ethereal tannin divides itself into 
three layers: the lower layer is a solution of tannin in the 
aqueous ether ; the second, a solution of tannin in ethereal 
water ; and the third is ether, nearly pure, containing very 
little tannin. 

Thus it results, that by covering coarsely pulverized gall-nuts 
with anhydrous ether, there exudes some ether slightly charged 
with tannin ; with ether containing water the liquid divides 
itself into three layers similar to those described above. With 
a mixture of ether and alcohol there runs a homogeneous solu- 
tion of tannin in the alcoholic ether. 

The extraction is made in a displacement apparatus, cold. 
Pelouze employed the. apparatus of Robiquet and Boutron as 
used for the preparation of amygdaline. Fig. 5 represents this 
digester. It is an elongated glass vessel A, having an orifice 
at the top, which is fitted with a ground glass stopper, and 
contracting towards the other extremity, which fits tightly into 
the neck of a bottle or matrass B, which receives the extract. 
Sometimes the lower bottle has a second tubular opening, D, for 
the purpose of receiving a cork furnished with a tube, to which 



101 



THE MANUFACTURE OF LEATHER. 



a connector, 
taclied to a 

Fi?. 5. 



c, of rubber is appended, the other end being at- 
similar tube fitted in cork which closes the top 
orifice. Between F and G is the pulverized 
gall, and in E is a little batting of cotton. 
This adaptation causes the filtration to take 
place more readily, whilst it prevents con- 
tact with any further quantity of air beyond 
what is contained in the apparatus. After 
the space between F and G has been filled 
with coarsely pulverized gall-nut, or two- 
thirds of the space of the vessel A can be 
so filled if desired, pour in a mixture of 9 
parts of ether and 1 part of water, so'as to 
cover the solid substance with a liquid 
column of a few centimeters. After twenty- 
four hours' contact, and after having agitated 
the mixture, the liquid is run oft' into the 
lower vessel by putting the tube at the top 
of the eking-piece in communication with 
the lateral tube of the lower vessel at D, by 
means of the gum tube c. This liquid di- 
vides itself into two distinct strata, the lower 
of which is a thick and syrupy solution of 
tannin in the slightly hydrated ether ; the 
upper stratum is a very weak solution of tannin and gallic acid in 
the ether. The upper layer is decanted, while the lower one is 
washed with a little ether and evaporated by placing the exsic- 
cator above or over a warm sand-bath, or under the receiver of 
an air-pump, or steaming water, or by putting it on the stove in 
shallow vessels. The tannin remains in the form of a swollen 
yellowish, amorphous, friable mass, which may be purified by 
dissolving it again in very little water, adding some ether and 
evaporating the syrupy layer which separates, and drying it at 
248° to 266° F. 

To exhaust gall-nuts Mohr uses a mixture of 4. parts of ether 
and 1 part of alcohol, or equal parts of the two liquids. The 
ether is distilled and then it is dried. 




VEGETABLE TANNING MATERIALS. 105 

The -industrial preparation is effected by one or another of 
these methods with appropriate apparatus. 

Thus obtained the tannin presents itself in the form of an 
amorphous, yellowish, friable mass, odorless, of an astringent 
taste, very soluble in water, hardly soluble in ether. The 
aqueous solution has an acid reaction ; put in contact with 
animal membranes (skins, etc.), it loses its tannin which fixes 
itself on the membrane to form an insoluble and imputrescible 
compound. The solutions of gelatine precipitate it also, form- 
ing a combination. 

Another modification of the method just detailed was intro- 
duced by Doraine, and offers the advantage of yielding a larger 
product, while it admits also of being applied on a large 
scale for the purposes of the manufacturer. He places the 
powdered galls in a damp cellar for several days, during which 
they absorb moisture ; the powder is next transferred to a wide- 
mouthed jar, and made into a paste with ether of a spec' fie 
gravity 0.75. After this the vessel is hermetically closed, and the 
contents allowed to digest for twenty-four hours. At the expi- 
ration of this time the pasty contents are transferred to a strong 
linen bag and subjected to gradual pressure, when the ethereal 
extract of tannin, having a dark syrupy consistence, flows oft' 
into the receiver. This liquid must be evaporated to dryness 
at a gentle heat, by which the tannic acid is left in the form of 
light-colored resin-like scales. The compressed residue is 
further treated with ether, to which six per cent, of water is 
added in the same manner as when preparing the first extract, 
and on expelling the fluid by a gentle heat, a residue of tannin 
is obtained. It is, indeed, more impure than the above, as it 
contains chlorophyll, volatile oil, and gallic acid ; still the tan- 
nin thus prepared answers very well for many industrial pur- 
poses. 

Sulphuric, hydrochloric, arsenic, and phosphoric acids, marine 
salt, or acetate of potash, separate the tannic acid of the aqueous 
solutions, concentrated under the form of insoluble combina- 
tions. Heated tannin melts and decomposes at about 410° to 
419° F. in carbonic acid, into pyrogallic acid and metagallic acid ; 
the proportions of these two acids vary with the temperature. 



106 THE MANUFACTURE OF LEATHER. 

At 482° F. raetagallic acid only is obtained. Heated in a platinum 
cap on a Bunsen burner it melts, swells, ignites, and burns with 
a clear flame, leaving a residue of charcoal. Ozonized air 
browns it and fluidifies it, and terminates by converting it en- 
tirely into carbonic acid and water. Aqueous solutions of tan- 
nin absorb ozone energetically and become of a brown-red ; by 
a more lengthened action of the ozone the color becomes clearer 
and there is very soon left but little of the substance in solution. 
Before this stage we ascertain the production of oxalic acid and 
of a substance which reduces the cupro potassic liquor.^ 

A weak aqueous solution of tannin absorbs the oxygen, while 
freeing an equal volume of carbonic acid; at the same time it 
is troubled by the deposit of gallic acid. 

Tannin, dissolved several times in water and evaporated by 
heat, transforms itself gradually, by contact with the air, into a 
brown insoluble substance (oxidized tannin of the ancient chem- 
ists). Oxygenized water and oxygenized essence of turpentine 
have no action. A solution of iodic acid reacts even when cold 
on the tannin with the production of carbonic acid mixed with 
a little oxide of carbon. Bromine reacts briskly and gives a 
brown resin. Clilorine attacks tannin also and colors its solu- 
tions brown ; iodine finely pulverized dissolves in water charged 
with tannin. 

Concentrated sulphuric acid dissolves tannin with a lemon- 
yellow tint or yellow-brown, passing to purple-red when hot, 
freeing sulphurous acid ; then the color becomes brown. 

Tannin boiled or digested while hot with weakened sulphuric 
acid is transformed into gallic acid (Liebig). According to 
Strecker,^ some glucose is separated ; at the same time, also, 
some traces of ellagio acid and ulmic matters. 

According to this Strecker considered tannin as a glucoside, 
and gave it the formula G^tK^X)^. He represented his de- 
composition by the equation: C.^jB.22^„ + 4:KJJ~SQjliJ^^-\-C^ 

^ Gorup-Bisanez, Ann. der Chem. u. Pharm., ex. 106. 

2 Annal. der Chera. u. Pharm., Ixxxi. 243 ; xc. 328 ; Cheiu. Soc. Quart. 
Journ., V. 102 ; Phil. Mag. (4) viii. 157. 



VEGETABLE TANNING MATERIALS. 107 

More recent experiments have proved that tannin must not 
be considered as a glucoside, and that the formation of sugar 
was due to the accidental presence of glucosides foreign to its 
real composition. According to Rochleder and Kawalier, tan- 
nin boiled with hydrochloric acid, protected from contact with 
air, furnished variable proportions of ellagic acid and of sugar. 
Nitric acid attacks tannin in watery solution, by coloring at 
first the liquor reddish-yellow, and lastly producing oxalic 
acid. 

A solution of tannin increased with a solution of osmic acid 
at 3 per cent, takes a dark-blue tint and leaves after evaporation 
a dark-blue residae. This residue, treated by the osmic acid 
solution, produces oxide of osmium and a liquor which, being 
increased with ammonia, is red-brown and produces by evapo- 
ration sonie crystalline needles formed of a mixture of oxalic 
acid and probably of suberic acid, also some ulmic matter.^ 

According to Rochleder and Kawalier,^ tannin heated with 
alkalis in a current of hydrogen, splits into gallic acid and a 
gummy matter. Hydrate of baryta furnishes under the same 
circumstances some gallic acid and some glucate of baryta. 
According to Liebig, potash transforms tannin into gallic acid, 
which a lengthened ebullition with potash converts into carbonic 
and pyrogallic acids. Being boiled for a few hours with its 
weight of neutral sulphate of potash and of soda and 12 parts 
of water, there is a formation of 5 to 6 per cent, of a body which 
possesses the composition of sugar, without having its properties. 
(Kuapp.) 

Chromic acid in aqueous solution, while hot, decomposes 
tannin completely, freeing carbonic acid; bichromate of potash 
precipitates it in yellow-brown or black. 

Peroxide of manganese boiled with tannin, with or without 
sulphuric acid, disengages carbonic acid and produces a brown 
extractive mass. Tannin reduces permanganate of potash 
solutions by taking from it about 0.6 part of oxygen for 1 part 
of tannin. 

• Bontlerrow, .Journ. Prac. Cliem., Ivi. 207. 
2 Wiener Akadem. Ber., xxv. 558. 



108 THE MANUFACTURE OF LEATHER. 

It acts as a reducer on ferric salts, and the salts of copper, 
mercury, and of silver, by bringing them back to the inferior 
degree of oxidization or by precipitating the metal. 

The impure tannin solutions, such as are obtained by a simple 
infusion of gall-nut, modify themselves when kept in contact 
with the air ; some carbonic acid is freed at the same time that 
there is a production of gallic acid and of allagic acid on account 
of a kind of fermentation, called gallic fermentation. 

Constitution of Oallotannic Acid. — The experiments of Strecker 
induced that chemist to consider the tannin of the gall-nut as a 
glucoside of gallic acid. The more recent researches of Schiff 
are contrary to this opinion. In fact, Schiff has succeeded in 
synthetically preparing tannin free from sugar, starting from 
the gallic acid. This fact had already been surmised by Lowe, 
but he did not give it its real significance.^ 

According to Schiff, gallic acid crystallized and dried at 50° F., 
treated at 212° to 248° P. with oxychloride of phosphorus, dis- 
engages hydrochloric acid. There is a formation of a yellow- 
powder which is washed with anhydrous ether and dissolved in 
water. After twelve hours we separate a certain quantity of 
unattacked gallic acid ; the liquid is precipitated with marine 
salt ; the emplastic precipitate is washed in salt water, then dis- 
solved in absolute alcohol ; several times its volume of ether is 
added to the solution ; it is filtered and the ether is distilled ; 
lastly it is dried. The residue presents all the properties of 
tannin and may be converted into crystallized gallic acid by 
ebullition with hydrochloric acid. According to these experi- 
ments tannin should be digallic acid : — 

/cooh )cooh 

ChHA=c,h,]oh-o-c,h, [oh 
(oh )oh 

Schiff has analyzed two tannates of lead obtained with 
acetate of lead used in excess or in insufficient quantity ; the 
one answers to the formula CjJI^PbjOg, and the other to the 
formula C,,H,Pb,Og + 2 H,0. 

> LiJwH, Journ. Prac. Chern., cvii. 464; H. Schiflf, Deutsch. Chem. Gesel., 
1871, 231 and 9G7. 



VEGETABLE TANNING MATERIALS. 109 

The new formula of tannin is confirmed by the analysis of the 
tetracetic derivative formed by the action of the acetic anhy- 
dride on the tannin, C,^Hg(C2H30)409, a colorless body, crystalliz- 
ing in peaks, having the form of cauliflower, hardly soluble in 
water, soluble enough in boiling alcohol, and not reacting any 
longer on ferric salts. Concentrated sulphuric acid converts it 
in rufigallic acid at 212° F. 

Eufigallic acid should be the anhydride of tannin or of gallic 
acid and should answer to the formula Cj^HgOg. 

According to all these results, it is probable that vegetables 
containing tannin under the formof apolygallic glucoside are very 
alterable and of which a portion v/ould remain undecomposed 
in ordinary tannin. 

Tannomelanic Acid. — According to Biichner, tannomelanic acid 
is obtained, as a product of the decomposition of ordinary tannin, 
by a prolonged ebullition of a solution of gallotannate of potash. 
The tannin is dissolved in a boiling solution of carbonate of 
potash of a density of 1.27, as long as there is any eftervescence ; 
then the liquid is kept boiling until a testing quantity, increased 
with acetic acid, remains limpid after cooling. It is supersaturated 
with acetic acid, and it is .evaporated to a dry state by means of 
steaming. The residue is exhausted by alcohol, which dissolves 
some acetate and some gallate of potash. The residue is 
dissolved in water and the solution is mixed with acetic acid 
and acetate of lead, which causes a precipitation of tannomelanate 
of lead under the form of a brown-black powder. 

The composition of this acid appears^ to be represented by the 
formula CgH^Og, and its formation at the expense of the gallic 
acid would be explained by the equation G^'K^O^+O—Q^Jd.^ 
+ CO, + H,0. 

Tanno'pinic Acid. — Eochleder and KaAvalier^ give this name 
to a derivative of tannin which is found towards spring in the 
needles of the Scotch pine. The alcoholic extract distilled after 
adding water, furnishes an aqueous liquor from which some 
resin has separated. This liquid is precipitated by fractioning 

' Biichner, Am. Chem. u. Pharm., liii. 373. 
2 Wiener Akadem. Ber., xxix. 22. 



110 THE MANUFACTURE OF LEATHER. 

with neutral acetate of lead. The precipitate is dissolved with 
weakened acetic acid, the solution is precipitated with basic 
acetate of lead, and the precipitate suspended in water is decom- 
posed bj sulphuretted hydrogen. The hot aqueous solution 
of this acid oxidizes rapidly in the air. 

The authors named give it the formula C28H3oO,g(?). 

Tannoxylic or Rufitannic Acid. — Product of the oxidation of 
gallic acid under the influence of alkalis. 

To obtain it, dissolve some tannin, cold, in a moderately con- 
centrated solution of potash ; the liquid is left to itself, in don- 
tact with the air, until it has taken a dark red-brown tint, then 
precipitated with acetate of lead ; the tannate of lead mixed 
with the tannoxylate is taken out by means of hot acetic acid ; 
the insoluble residue is treated hot with a mixture of alcohol 
and sulphuric acid. A dark red solution is thus obtained, of 
which the acid is taken by distillation of the alcohol, under the 
form of an amorphous brown-red mass. Its composition ap- 
pears to answer to the formula C^H^^Og. There would be pro- 
duced at the expense of the gallic acid^ by addition of oxygen 

Many of the other tannic acids, which have thus far not been 
thoroughly examined, show properties corresponding more or 
less in their behavior. 

We will here consider somewhat closer the quercotannic acid 
as being highly important to the tanner. 

This was formerly considered as identical with gallotannic 
acid, but it differs materially in its composition, properties, 
and products of decomposition. Stenhouse showed conclusively 
that quercitannic acid, on decomposition Avith sulphuric acid, 
does not give gallic acid, nor pyrogallic acid, when subjected to 
dry distillation. The chemical formula of quercotannic acid is 
according to Grahowsky^ and Oser^ CguHjoOj,. It forms a yellow 
brown amorphous mass readily soluble in water and alcohol ; 
the aqueous solution is precipitated with sulphuric acid in red- 

' Buchner, Am. Chem. Pharm., liii. 369. 

2 Wiener Akadem. Ber., 1867, Ivi. 387. 

3 Wiener Akadem. Ber., 1876, Ixxii. 165, und Handwoerter buch der Chem., 
Bd. ii. 



VEGETABLE TANNING MATERIALS. Ill 

brown flakes. With solutions of glue, tartar emetic, and 
quinine, it gives precipitates like gallotannic acid. It changes 
ferric chloride into a deep black fluid, which is colored red bj 
an addition of sodium carbonate. 

Quercotannic acid is easily oxidized by exposure to the air, 
especially when in alkaline solution ; 100 grms. of the acid 
absorb 12.8 grms. of oxygen. 

By boiling with dilute sulphuric acid quercotannic acid (Gj^ 
Hgi.O],) is resolved, with absorption of water, into quercus red,^ 
Cj^HjgOg, and sugar, CgHj^Og (Oser^). According to Grabowsky 
quercus red is Cj^Hj^O^, the difference appearing to be due to 
the temperature and duration of decomposition or the quantity 
of acid used. 

Quercus red is a red amorphous body insoluble in water and 
ether, but soluble in water and ammonia. Water precipitates 
it from an alcoholic solution, and acids from an ammoniacal 
solution. 

Quercotannic acid in aqueous solution compounded with 
cinchonin acetate gives a precipitate with the formula Cj^H^^lSr, 
0{Q^^Jd^^? In washing the precipitate it is not insoluble in 
water but dissolves more readily in acetone. This solution is 
precipitated with solution of barium acetate in acetic acid.^ 

Besides quercotannic acid, oak bark contains quercus hitter or 
quercin as Gerber^ terms it. It is a crystallizable bitter sub- 
stance which Gerber obtained from a decoction of bark pre- 
pared with milk of lime after precipitation with potassium 
carbonate and evaporation. The small white crystals possess 
no odor and a very bitter taste. They dissolve in thirteen parts 
of cold water, but more readily in warm, and also in aqueous 
but not in absolute alcohol, and in ether and oil of turpentine. 
From hot hydrochloric acid or acetic acid they crystallize with- 
out change, but are colored by nitric or sulphuric acid. 



■ The well-known fact that oak-tanned leather on coming in contact with 
acids, turns red, may be traced to this. 

2 Wiener Academ. Ber., 1876, Ixxii. 165. 

3 Wiener Akadem. Ber., 1876, Ixxii. 165. 

* Handwoeterbuch der Chemie, Bd. ii. 1046 ; Berzelius's Jahresber., xxiv. 635. 



112 THE MANUFACTURE OF LEATHER. 

We will here mention the quevphlohai^jhene^ which resembles 
quercus red, and which is prepared by treating bark completely- 
extracted with water with ammonium, and precipitating with 
hydrochloric acid. Its composition corresponds to the formula 
C^^Hg^Oj., or nearly Cj^Hj^O^. Querphlobaphene dissolved in 
as little ammonium as possible gives with calcium chloride or 
barium chloride as precipitates: Cj^H^^Oj^Ca, or CjoHj^Oj^Ba. By 
fusing this body with potassium hydrate, it yields phloroghicin 
and protocatechuic acid, and sometimes a small quantity of 
pyrocathechin.^ 

The property of tannic acid of forming insoluble combinations 
with earthy alkaline salts is of practical importance in tanning. 
By the use of hard water a loss of tannic acid may be caused by 
the formation of insoluble barium or lime combinations with the 
tannic acid. As the loss thus caused is by no means a small 
one, it is recommended for tanneries using very hard water to 
purify it before leaching the bark.^ 

A further property of tannic acid deserving consideration is 
that it can be brought into fermentation by fungi and ferments. 

In tanneries where scrupulous cleanliness is not the rule, it 
is frequently the case that the edge of the ooze vats is covered 
with a rank fungous vegetation. Many tanners cannot know 
that these fungi decompose tannic acid into acetic acid, lactic 
acid, etc., or they would surely be more careful to remove this 
foul matter. 

Only since we have acquired the knowledge how to deter- 
mine tannic acid analytically, has it been found that plants may 
contain very varying quantities of tannic acid in their separate 
parts, or in the different stages of their development.^ 

1 Wiener Akadem. Ber., 1867, Ivi. 387. 

2 Aniial. der Chemie u. Pharinacie, cxlv. 1. 

3 In many tanneries the water is filtered through exhausted tan, whicli 
though quite suitable, is rather a laborious method. Tlie small quantity of 
tannic acid still contained in the tan precipitates the lime and magnesia salts of 
the water. The principal objection to this method of purifying the water is that 
organic acids such as acetic, lactic, propionic acids, etc., may get into tlie water, 
and that by using such water for leaching fresh tan a decomposition of tlie tannic 
acid may be caused by the ferments. 

* Through researches made by Schulze (Dingler's Polyt. .Journal, clxxxii. 158), 
it was found that oaks twenty-four to thirty years old yield tan containing a very 



VEGETABLE TANNING MATERIALS. 113 

In perennial plants the roots, barks, and brandies of most 
trees contain tannic acid, as frequently do also the leaves, folli- 
cles, and fruits of bush-like and tree-like plants, especially when 
full-grown. Tannic acid was formerly supposed to be the pro- 
duct of a commencing process of decomposition of the cell 
substance, and its formation a peculiar decomposing process of 
the cell membrane, but recent researches have proven that 
tannic acid is in most cases a primary product of vegetable 
life, as shown by its frequent occurrence in young plants while 
yet in the first stage of development. 

The action of the different tannic acids towards the coriura or 
leather skin varies greatly. 

Observations of practical men have shown that vegetable 
substances the tannic acid of which, when heated, forms pyro- 
gallic acid, furnish leather less capable of resisting water, and 
consequently less suitable for the consumer, than tannic acids 
which, when heated, yield pyrocatechin. 

The extractive substances, such as coloring matter, resins, 
pectine, and pectic acid, organic acids, sugar, etc., exert a material 
influence upon the value of a tannic acid. The coloring matter, 
for instance, may injure the appearance of the leather, and the 
resins and other extractive substances the quality. 

The influence exerted by resins, pectine substances, etc., has 
unfortunately been but little studied by chemists, and the judg- 
ment of this matter is limited. 

Section II. Vegetable Tanning Materials. 

But few of the large number of vegetables containing tannic 
acid are used in tanning, though in modern times the number 
has been largely increased by diligent researches m-ade with a 
view to obtain cheaper tanning materials. 

We shall here briefly discuss the most important tanning 

high percentage of tannic acid, while that from oaks eighty to one hundred and 
twenty years old contained far less. But the percentage of tannic acid in tlie 
younger trees varies frequently so much, that that contained in the older ones 
may often be as large as in the younger trees. 



114: THE MANUFACTURE OF LEATHER, 

materials, first mentioning the inspissated vegetable juices which 
are imported. 

Rutea is the inspissated juice of Rutea formosa^ and is only 
used for tanning in the northwest of India. 

Kino is the inspissated juice of Pterocarpus erinaceus and 
onarsupium. Kuraerous varieties of kino are known in com- 
merce, though the principal ones are those coming from Africa 
and Malabar. The African kino, which is the best, and but 
seldom found in commerce, is the inspissated juice of Pterocaiyus 
erinaceus. 

The Malabar or East Indian kino is derived from Pterocarpus 
marsapium^ a tree indigenous to After India, Malabar, and 
Ceylon. Both varieties of kino are very rich in tannic acid, 
that of the latter being identical with gallotannic acid, it 
yielding, on heating, pyrogallic acid. On account of its high 
price, and the disagreeable red color it imparts to the leather, 
this tanning material is but little used. 

Gambier is an extract from the leaves of Uncaria yamhir. 
It forms cubical pieces -^ to ^ inch thick of a light and dark 
rust or sometimes gray color, which float upon water and are 
very friable. Gambier is slightly soluble in cold water, but 
readily in hot. Its percentage of tannin is quite high. 

Catechu^ or terra jap)onica^ is the dry extract from the core wood 
of a mimosa, Acacia catechu^ growing in the East Indian islands. 
Its principal constituents are : Catechin, a brown substance 
which can be precipitated from its solution with glue, and cate- 
chutannic acid, which appears to be formed from the catechin by 
exposure to the air. It colors ferric oxide green, and gives a 
green-black precipitate with ferric salts. A judgment of the 
value of catechu is formed by its external color, hardness, taste, 
solubility ia spirit of wine, etc. Genuine catechu melts upon 
the tongue, while non-genuine sticks to it. Adulterations with 
blood, sugar, etc., can be detected by the characteristic odor of 
these admixtures when burnt. The leather produced with 
catechu is not of a particularly good quality, it being of a dark 
color, permeable to water, spongy, and at the same time hard. 

Gall-nuts are the richest in tannin of all tanning materials. 
They are morbid excrescences of the leaves and young branches 



VEGETABLE TANNING- MATERIALS. 115 

of Quercus infectoria^ Oliv., formed by the puncture of gall-flies 
{Cynips gallse tinctorta), belonging to the Hymenoptera^ for the 
purpose of depositing their eggs. As the latter develop, excres- 
censes called galls or gall-nuts are formed on the jDunctured 
places by the exudation of sap and enlargement of the cells. 
The larvae which are inclosed in the galls are supported by the 
juices of the plant until they become perfect insects, when they 
perforate the gall and escape. When this happens the excres- 
cense loses much of its astringent principle and becomes lighter 
in color and finally entirely white, while if collected before the 
entombed insect is completely developed the galls are of a dark 
to blackish color, and much richer in tannin. 

The latter are known in commerce as green ycdls^ and come 
from Aleppo, Smyrna, and Mesopotamia. 

Gall-nuts are also imported from Cypria^ Karamania^ etc., 
though they are not so good as the Aleppo galls, with which 
they are sometimes mixed. 

European galls, formed by the puncture of other species of 
gall-flies of other varieties of oaks, are not so good as the Aleppo 
galls. They come from the Morea, Italy, Hungary, and Istria. 
Gallotannic acid is, as previously mentioned, the most accurately 
known. 

OaUs (Knoppern) formed by the puncture of a gall-fly {Cy- 
nips quercus calycis) in the young fruits of Quercus pedunculata. 
They are principally collected in Hungary, Dalmatia, and Sla- 
vonia, and contain, besides a small quantity of gallic acid, much 
tannin closely resembling gallotannic acid. The percentage of 
tannin amounts, according to Mueller, to as much as 50 per 
cent. 

Chinese Gall-nuts form irregular roundish bulbs of the size of 
a hazel or walnut, which inclose the insect. Their rind is 
smooth and felt-like, of a gray or reddish color, and very thin, 
and consequently fragile. They show no vegetable structure, 
but a dense, brilliant, resinous fracture, and are said to be de- 
rived from a species of sumach. They are much in dem.and on 
account of their high percentage of tannin, which, according to 
Mueller, amounts to as high as 65.5 per cent. 

Rove. — The article known by this name, which is brought 



116 THE MANUFACTURE OF LEATHER. 

into commerce ground and pressed in bricks, is the so-called 
Bassora gall-nut, and is found in Persia and Asia Minor. It is 
principally exported by way of Smyrna. It contains about 27 
per cent, of tannic acid. Mixed with oak or fir bark, it is, 
according to Eitner, well adapted for tanning sole leather. 

Sumacli consists of comminuted leaves, stems of blossoms, and 
branches of several Rhus species, such as Rhus coriaria^ R. co- 
tinus, R. glahrum, R. canadense, R. iyjphinum^ R. pentaphyllum^ 
Arbutus uva ursi, Coriaria mystifalia. 

The following varieties are found in commerce : — 

Sicilian Sumach., from Rhus coriaria^ is the most valued. It is 
divided into two qualities, the best being of a, greenish -yellow 
color, while the inferior variety is of a more rusty-yellowish 
color, and has less smell and less tannic a«id. 

Italian Sumach, which is also derived from Rhus coriaria, is a 
dirty-green powder. It is far inferior in tanning capacity to 
the Sicilian variety, it being besides frequently adulterated with 
sondro leaves. 

Spanish Sumach. — Three varieties of this occur in commerce, 
viz: Malaga, or Priego, Malino, and VaUadolid, the last two be- 
ino" of less value than the first. 

l^yrol Sumach, the odor of which resembles that of oak bark, 
is derived from the leaves and stems of Rhus cotinus. Like the 
Italian and Sicilian sumach, it is frequently adulterated w^ith fig 
leaves. 

French Sumach (from Coriaria mystifolia). 

There are four varieties : Fauvis, Redoul, Donz^re, and Pudis 
sumach, the last two being less liked than the others. 

The " Tezera''' sumach, used by the Arabs for tanning morocco 
leather, is derived from Rhus pentaphillum. 

American Sumach is derived from Rhus canadense and R. glah- 
rum. Large quantities of it are used in the United States, 
nearly all the morocco manufacturers mixing it with an equal 
quantity of Sicilian sumach to form the tanning liquor, which is 
forced through the goat skins by hydrostatic pressure. Sumach 
is also used in tanning buffed leather. Large quantities of 
American sumach are shipped from Georgetown,, I). C, and 
Alexandria, Va. 



VEGETABLE TANNING MATERIALS. 117 

Swedish Sumach is prepared from the leaves of the bear-berry 
{Arbutus uva-ursi). 

It is not yet definitely determined whether all the different 
varieties of sumach contain the same or different kinds of tannic 
acid, though the latter is the most probable. 

The tannic acid contained in the Sicilian sumach is, according 
to Stenhouse,* identical with gallotannic acid. In old sumach, 
the larger portion of the tannic acid has been converted into 
gallic acid and sugar. 

Leather prepared with sumach possesses but little capacity for 
resisting water, and is therefore principally used for the uppers 
of ladies' fine shoes, book-binding, portfolios, pocket-books, 
linings, bindings, skivers, etc. 

Valonia is the acorn-cup of Quercus seyilops^ prickly-cupped 
oak, a tree growing in abundance in the islands of the Grecian 
Archipelago, The tannic acid of valonia is not known in a 
pure state, as it always contains gallic acid. The use of valonia 
has recently much increased in Europe, it being especially em 
ployed, mixed with oak tan, for sole-leather in the last two 
spreadings of the hides in the binders. Leatlier prepared with 
valonia, is said to be harder and« less permeable to water than 
that made with oak bark, its weight being also increased. The 
price of valonia which contains a considerable percentage of 
tannic acid, is low compared with that of tan, and it is much 
used by English tanners. 

Divi-divi consists of the dried pods of a bush {Csesalinnia 
coriaria) indigenous to South America. Leather tanned with 
the extract becomes very soft and spongy, and on exposure to 
the air assumes a more or less brown to brown-red color. The 
extract of the divi-divi pods is also brought into commerce. The 
tannic acid differs from the gallotannic acid, and, when heated, 
does not yield, like the latter, pyrogallic acid. 

Myrohalans^ the dried fruit of Terminalia chebula^ is princi- 
pally collected in India. The fruits exported by way of Cal- 
cutta are of a roundish shape, gray-black color, and hard and 
astringent. They contain, principally in the husk, a consider- 

1 Dingl. Polyt. Journ. clxv. 150. 



118 THE MANUFACTURE OF LEATHER. 

able quantity of gallic acid, which, according to Stenhouse, dif- 
fers so far from gallotannic acid as not to yield, on boiling 
with dilute sulphuric acid, gallic acid, but a reddish-brown sub- 
stance insoluble in spirit of wine. 

Myrobalan is used in Europe in tanning as an addition to 
oak bark. 

Buhlah is the husk of the fruit of Acacia hamhtila. It comes 
from India, and contains considerable tannic acid. 

Of the other foreign materials containing tannic acid, which, 
on account of their high price, etc., are more extensively used 
in dying and coloring than tanning, we will mention : — 

Logivood^ which is derived from Hsematoxylon carri'peacliionu.ra^ 
a Csesalpina growing wild in Yucatan and some of the West 
Indies. 

Fustic^ obtained from Moms tinctoria. It contains a peculiar 
tannic acid, moritannic acid, or macherin, which on heating 
yields pyrocatechin. It is only used for coloring leather. 

Weld [Reseda luteola) is a plant belonging to the Resedacese, 
which grows wild in all European countries, though it is occa- 
sionally cultivated in Southern France and Germany, 

The following barks are also made use of in tanning, although 
not so extensively as hemlock and oak barks : — 

Larch hark {Larix Europsea). — This bark yields a material 
relatively poor in tannin. It contains, according to Dav}'^, 1.6 
to 2 per cent, of tannic acid. The bark is used in England and 
Ireland for tanning sheep-skins. 

Fir barh [Pinus ahies) is principally used in Europe, in 
Austrian, Bavarian, Hanoverian, and Upper Svvabian tanneries. 
It is claimed to be especially adapted for " plumping," or the 
so-called preparatory swelling and tanning of hides. 

Hemloch bark is obtained from Abies Canadensis. 

The baric is light, has a somewhat balsamic odor, and a 
slightly astringent taste. The tannin is colored green by ferric 
salts, and brown by potash lye. It is the most important tan- 
ning material in America, where it is much used for tanning 
both sole and upper leathers, two-thirds of all sole and upper 
leathers produced in the United States being tanned with it. 
This variety of leather has been only lately appreciated in many 



VEGETABLE TANNING MATERIALS. 119 

portions of Europe, and our exports of this variety of leather 
are constantly increasing, but, as has been stated, not so rapidly 
as they ought to do considering its wearing qualities and its 
cheapness, A mixture of hemlock bark and oak gives a very 
serviceable leather, termed " union tannage." 

An extract of hemlock bark goes into the European markets 
under the name of American hemlock extract^ and it is also em- 
ployed in portions of this country where bark is scarce. 

It is chiefly prepared from thick bark, since the greatest yield 
of tannin is, according to Eitner, obtained from the rind, and not 
from the pulp, an analysis of the latter showing 7.7 per cent, 
of tannic acid, and of the former 11.3 per cent., while the entire 
bark yielded 10.1 per cent. 

Oak harks, from Quercus monticola of Michaux, rock chestnut 
oak, and Q. tinctoria, yellow-barked oak, are the most esteemed 
for tanning purposes in the United States. The best is the 
first-named variety, and the prime quality is derived from the 
Blue Ridge, which is the most easterly ridge of the Allegheny 
Mountains. The principal tanneries using rock' chestnut-oak 
bark are located in the State of Yirginia, the western portions 
of the Carolinas, and in Tennessee ; the bark in the latter State 
being derived from the Cumberland Mountains. In tanning it 
is used unmixed, and gives a beautiful " bloom ;" the sole leather 
produced with it being always in demand for both home con- 
sumption and for export. The bark of the yellow-barked oak 
is in tanning commonly mixed with red-oak bark, as the color 
which the former yields when used alone is objectionable. 

The inner bark of the Q. tinctoria is the quercitron of dyers. 
The barks of the Q. alha, white oak, and Q. rubra, red oak, are 
not esteemed in tanning, the first being poor in tannin and the 
second imparting an undesirable color to the leather. 

Walnut hark from Juglans reyia gives a very soft leather, but 
can only be obtained in small quantities. 

Lorahardy poplar hark gives a light-brown leather with an 
odor resembling that of Russia leather. 

Elm hark, from Uhnus campestris, is especially used in Norway 
for manufacturing the beautiful Norwegian glove leather. 



V 



120 THE MANUFACTURE OF LEATHER. 

Horse-chestnut bark from jEscuIus hippocastunum. The bark 
of this tree contains a tannin which is colored intensely green 
by ferric oxide. Besides the tannin, which is also found in 
other parts of the tree, the bark contains fraxin, fraxetin, ses- 
culin, sesculetin, and aesculetin hydrate, a small quantity of a 
peculiarly yellow crystalline body and a pectine substance 
which is decomposed into formic acid, oxalic acid, and protoca- 
techuic acid by boiling potash. The leaves of the horse chest- 
nut^ contain also tannic acid, wax, a variety of rosin (C^gHg^O,^) 
and a resinous substance (Cj^H^gO^) possessing a peculiar odor 
of frankincense. The young leaves and buds contain a peculiar 
tannin to which Rochleder has applied the term '■'■ pjhyllocitannic 
acidr 

JEsculotannic Acid? — Different kinds of tannic acid are found 
in the horse chestnut, sesculotannic acid (G^gHg^Oj^)- occurring, 
according to Rochleder, in the bark, leaves, flower-buds, ripe 
and unripe seeds, roots, and the trunk. In a pure state it forms 
an almost colorless amorphous powder readily soluble in water, 
spirit of wine, and ether. By the action of the air and alkali, or 
substances containing oxygen, such as chromic acid, it is decom- 
posed into a brown body having the constitution CjgH220j3. 
Fusing with potash changes ^esculotannic acid into phloroglucin 
and proto-catechuic acid. Ferric chloride colors the tannic acid 
green. 

An aqueous extract of the bark comes into commerce under 
the name of " horse-chestnut extract^ The percentage of tannic 
acid in the extract varies according to its specific gravity. It 
is at present much used in Germany and other portions of Europe 
as an addition in oak-bark tanning, and is said to give good 
leather. It is considerably cheaper than quercotannic acid. 

Willoio Baric. — The following are the principal willow barks 
used in tanning: Salix alba, S. arenaria, S.fragilis, S. piayura^ 
etc. There is not much difference in the value of the barks, 
though it is claimed that barks containing salicin, as for instance 
that of S. purpurea, are not so good as others. The amount of 

1 Rochleder Wiener Akadem., liv. 24 bis 48 ; 236 bis 254 ; 604; 607 bis 657. 
8 Ibid., liv. 607. 



VEGETABLE TANKING MATERIALS. 121 

tannin varies from 6 to 16 per cent. In Russia willow bark is 
used for tanning Russia leather, and in Sweden and Norway for 
preparing the well-known Swedish glove leather. The tannic 
acid 'contained in willow barks colors ferric salts green, and, 
when treated with dilute sulphuric acid, yields sugar and possi- 
bly gallic acid, though this is donbtful. 

Alder Barh contains a high percentage of tannin, amounting, 
according to Gassincourt, to 36 per cent. 

Beech hark from Fagiis silvatica mixed with oak bark may be 
used as a substitute for the latter, but the resulting product is of 
an inferior quality. It contains, according to Davy, 2 per cent. 
of tannin, and besides a peculiarly red matter and a substance 
with an odor of vanilla. 

Proiaceee Barks. — The trees from which this bark is obtained 
are indigenous to the Cape and Australia. The principal ones 
are the Protea conocarpa (knotted tree) and Banksia serrata. 

The tannin of the latter imparts a beautiful violet-blue color 
to solutions of ferric salts, while that of the first colors iron- 
green. Both give a brown color with potash lye. 

jSnouha Bark. — The Aleppo fir [Pinus halepensis) yields two 
important tanning materials, namely, the snouba bark, and the 
scorzarosa. The first is the inner bark of the tree freed entirely 
from the rind, and comes from Tunis and Algiers. 

The scorza rosa is the rind of the same tree, obtained in 
Southern Italy, and especially in Sicily, from the living trees in 
a very rational manner, so that the flesh of the bark remains 
intact, and produces, like the cork tree, new bark, which is 
periodically taken ofi". Snouza bark contains 25 per cent, of 
tannin, and sco?-za rosa 13 to 15 per cent. The tannin colors 
ferric salts green, while it becomes brown by an addition of 
potash lye. 

Batanhy root is obtained from Krameria triandra., which grows 
in Peru. The root comes into commerce in a comminuted state, 
and is very rich in tannin, which is extracted with water, and 
theresulting solution used as an addition in tanning. The pro-, 
portion of tannin is, according to Peschir, as much as 42.6 per 
cent. It corresponds, according to A. Rabe,^ with the formula 

1 Pharm. Zeitung f. Russland, xix. 577. 



122 THE MANUFACTURE OF LEATHER. 

CgoHjoOg, It is not a glucoside, and passes, by the splitting off 
of H2O, over into ratanhy red CjoH^gO,,. 

Avens root, from Geumi urhanum, contains, according to 
Trommsdorff, up to 41 per cent, of tannin. Solutions of it have 
occasionally been used as an addition in tanning. 

Tormentil root and Sassafras root show a still higher percent- 
age of tannin, the first containing, according to Gassincourt, 16 
per cent, of it, and, according to Reinsch, up to 58 per cent. 
Both roots being very expensive are not often used for tan- 
ning. 

The wood of the Algarohia glandulosd of Gray, m.esquite oah, 
and Q. virens, live oah, contains much tannin in its entire mass, 
and is very successfully used in America in place of tan. 

Quebracho is obtained, according to a communication by C. 
Donath,^ in the province of Santiago from Aspido^Derma que- 
hracho. It is brought into commerce in blocks with a reddish- 
brown appearance upon the cutting surface. It costs about 
$2.75 per 100 lbs., and is said to contain about 20 per cent, of 
tannin. Before use it is cut into small pieces, which are ground 
to a fine powder by disintegrators. G. Fraude^ found in the 
bark of the wood an alkaloid to which he has applied the term 
aspidospermin G^^^^^O^, or Cg^H^gNgOg. Miintz and Schon 
claim that, by tanning with quebracho, good leather and weight 
are obtained. 

Mimosa. — Besides these the following tannins, the names of 
which we will only mention, have been proposed and occasion- 
ally used : Barks of Butea frontosa and Butea gibsonis, both 
indigenous to the West Indies; fruits of Balsamoharpon brevi- 
folium.^ bark of Eucahji:)tus ; Pangue, a root growing in India ; 
Pitnica granatum, etc. 

We have in the following compiled — 

' Dingl. Polyteclni. Journal, ccxxxi. 451. 

2 Ber. d. deutsch. cliem. Ges. 1878, 2189 ; Diugl. Polyteclni. Journal, ccxxxii. 
92. 

' Engl. Patentberichte, 1875, Ramsbaclier, Masurer. 



VEGETABLE TANNIKG MATERIALS. 



123 



The Percentage of Tannin contained i7i the various Tangling materials 
determined according to different methods. 

cent, according to Davy. 
Davy. 
Vauquelin. 
Solly. 
Guibonrt. 
Fehling. 
Bley. 
Fehling, 
Roder. 
Fehling. 
Peschier. 
Gmelin. 
Fehling. 
Fehling. 
Davy. 

Davy and Geiger. 
Esenbeck. 
Fehling. 
Davy. 
Davy. 
Davy. 
Davy. 

Gassinconrt. 
Gassinconrt. 
Fontenelle. 
Davy. 
Fontenelle. 
Fontenelle. 
Davy. 
Davy. 
Davy. 
Davy. 
Davy. 
Riggers. 
Gassinconrt. 
Gassinconrt. 
Gassinconrt. 
Gassinconrt. 
Davy. 

Gassinconrt. 
Gassinconrt. 
Gassinconrt. 
Reinsch. 



Bombay catechu 


. 55 per 


Bengal " 


. 44 " 


Kino . 


. 75 " 


Buted gum 


. 73.2 " 


Aleppo nut-galls 


. 65 ' 


<l (( n 


. 60 to 66 ' 


Chinese " " 


. 69 ' 


U tt IS 


. 70 ' 


Istrian " " 


. 24 " 


Valonia 


. 30 to 33 ' 


Ratanhy root 


. 42.G " 


" " 


. 38.2 ' 


Best oak bark . 


. 19 to 21 ' 


Old " " . 


. 9 to 16 ' 


Young '"' " 


. 15.2 " 


" " " (taken 


in spring) 22 " 


Gambier 


. 40 ' 


Fir bark 


. 5 to 7 ' 


Birch bark 


. 1.6 ' 


Beech " . 


. 2 ' 


Larch " . 


. 1.6 ' 


Hazel " . 


. 3 " 


Chestnut (America) 


. 8 " 


" (Carolina) 


. 6 " 


" (France) . 


. 4 '• 


" (Spain) 


. 0.5 ' 


Horse chestnut . 


. 2 " 


Lombardy poplar 


. 3.5 " 


Elm bark . 


. 2.9 • 


Ash " . 


. 3.3 ' 


Willow bark (Leicest 


iv) . . 6.8 ' 


" " (inner) 


. 16 ' 


" " (middle 


) . . 3 ' 


" " (branch 


es) . . 1.4 ' 


Weeping willow bark 


. 16 " 


Alder bark 


. 36 " 


Cherry tree 


. 24 " 


Cornel cherry . 


. 19 " 


Elder 


. 2.3 ' 


Apricot 


. 32 ' 


Pomegranate tree 


. 32 " 


Tormentil root . 


. 46 " 


Sassafras root bark 


. 58 ' 



124 



THE MANUFACTURE OF LEATHER. 



Snmacli (Sicily) 


. 16.2 per ct. according to Davy. 


" (Malaga) 


. 16.4 " " " Davy. 


a u 


. 10.4 " " " Frank. 


" (Carolina) . 


. 5 " " " Gassiucourt. 


" (Virginia) . 


. 10 " " " Gassincourt. 


Avens root 


.41 " " " Trommsdorff 



More recent examinations of various substances containing tan- 
nin give the folloioing results: — 
Fraas found in 100 parts of 



srarden 



Per ce 
Fall tormentils {tonnentilla erecta) 

" " " " from the marsh 

Dry fall tormentil root 
Sanguisorba officinalis . 
Polygonum bistorta 

" " spring , 

" " from the botanical 

" " leaves in the fall 

" " waste of roots 

Fall polygonum from the marsh . 
Summer polygonum from the marsh 
Willow bark from salix purpurea in the fall 
Fir bark from the second sap, 15 to 20 years old 
" " 20 to 30 years old . 
" " 30 to 40 " " , 
" " 40 to 50 " " . 
" " 80 to 100 " " . 
Bark cuttings from pine hop poles 
Aspen bark in the fall (12 years old) 
Birch bark (bet. pubesc.) 
Hippophae rhammoides, fall leaves 

" " young branches 

Old oak branch bark from thin branches in the 2d sap 
" " " " 1st " 

" " " medium «' " 2d " 

Field oak, 40 to 60 years old, 1st sap .... 
Crude oak bark covered with rind, 1st sap, 30 years' growth 
Inside of oak bark, 2d sap, 20 years' gi'owth 

" 1st " << " . . 

Inside layer and inside of bark, 1st sap, 24 years' growth 



nt. of tanain. 
20.5 
43.2 
20.0 

3.9 
17.1 
21.1 
17.0 

4.2 
16.0 
20.0 
26.4 

5.0 
10.8 

8.0 

7.5 
10.7 

8.7 

9.0 

2.6 

5.3 

5.0 

4.0 
13.3 

3.6 

8.0 
18.0 

9.2 

8.6 
14.6 
17.0 



Only a relatively small number of the many tanning materials 
enumerated in the foregoing are used for tanning on a large 
scale. The cause of this may be found partly in the conserva- 
tive bias of the tanners, and partly in the imperfect knowledge 



VEGETABLE TANNING MATERIALS. 125 

of the action of the various tanning materials upon the skin 
tissue. It requires extensive study to become thoroughly con- 
versant with the effects exerted by the various tannins and the 
extractive resinous substances accompanying them upon the 
skin tissue. 

In most countries only such tanning substances are chiefly 
used as are produced there in great abundance. ' In the United 
States, for instance, hemlock and oak bark are principally used ; 
in France, Germany, and England, oak bark ; and in Sweden, 
Norway, and Eussia, mostly the barks of birch, poplar, and 
alder, 

Valonia and mimosa are used as additions to the mentioned 
materials in Germany and England. Sumach is chiefly employed 
for the production of morocco and leather for pocket-book- 
makers' use. Catechu, gambler, and the other exotic substances 
have thus far been only experimentally used in the United 
States, but much more largely in Great Britain ; while quebracho 
and chestnut bark have only lately been employed on a large 
scale in England, German}'", and France. 

Practical experiments have shown that there is a considerable 
difference in the quantity of the various vegetable tannins men- 
tioned which is absorbed by the skin. Whether the greater ab- 
sorption is to be attributed only to the tannin or to the extractive 
and resinous substances accompanying it has thus far not been 
finally determined by experiments. But it may be reasonably 
supposed that the observed difference must be attributed partly 
to the larger or smaller absorption of extractive resinous sub- 
stances contained in varying quantities in the different tannins. 

We give in the following a few tables showing the quantities 
of tannin absorbed by the skin in using different tanning ma- 
terials. 

The folloioing quantities of tannin are required^ according to 
Anthon^ for the conversion of each 1 Ih. of skin into leather: — 

Of oak bark according to quality . . . . 2^ to 5 lbs. 

" oak leaves gathered ia May . . . . . . 5 " 

" alder bark 9 " 



' Fortschritt, xxvii. 212. 



126 



THE MANUFACTURE OF LEATHER. 



Of beech bark . 
" ash bark 
" aspen bark . 
" fir bark 
" maple bark . 
" acacia bark . 
" hazel bark . 
' ' cherry tree bark 
" larch bark . 
" mulberry tree bark 
" nut tree bark 
" willow bark . 
" nut-galls 
" valonia 
" sumxich 
" broom . 
" bilberry bush 
" cranberry bush 



. 9 lbs. 

5 " 

. 5 " 

. 4 " 

. 5 " 

. 5 " 

. 5 " 

. 5 " 

. 4 '■ 

. 6^ " 

• 1^ " 
4 to 5 ' • 
10 oz. 
1 lb. 

H "■ 

9 " 
1 " 
9 " 



Knapp^ communicates experiments made by Ludwig Kester. 
The skins as well as the tanned hides were only air-dried, but so 
that the comparison between skins and tanned hides, con- 
sequently the increase in weight, was as assured as possible. 





Weight of each two 


Increase 


in weight 


Con sun 


ption of 




calf-skius 


air-dried. 


by lanning. 


tanning 


material. 


Vegetable tanning 












1 part by- 


material. 












weight ot 




Raw. 


Tanned. 


Absolute. 


Per cent. 




air-dried 
raw skins 
parts by 
weight. 




lbs. 


lbs. 


lbs. 




lbs. 




Catechu .... 


2.16 


3.15 


0.99 


45.8 


4.4 


2.1 


Fir bark . . 






2.1B 


3.19 


1.04 


49.3 


39.36 


18.5 


Old oak rind . 






2.14 


3.198 


1.05 


49.4 


49.5 


23.1 


Young oak rind 






2.13 


3.22 


1.09 


51.0 


26.4 


12.3 


Nut-galls 






2.02 


3.14 


1.12 


55.4 


3.52 


1.7 


Divi-divi 






2.21 


3.45 


1.24 


56.2 


4.4 


2.1 


Tormentil . . 






2.34 


3.73 


1.39 


59.7 


19.8 


8.4 


Myrobalan . . 






2.19 


3.56 


1.37 


62.5 


4.4 


2.1 


Dohra bark 






2.09 


3.51 


1.42 


68.0 


4.4 


2.1 


iSuinach . . . 






2.23 


3.77 


1.54 


69.0 


9.9 


4.4 



According to these experiments, the quantity of tannin 
absorbed varies between 46 and 69 per cent. 



' Dingl. Polytechn. Journal, ccxxvii. 86. 



VEGETABLE TANNING MATEEIALS. 



127 



Prof. Miintz and Dr. C. Schoii^ also communicate experiments 
regarding the absorption of different tannins bj the skin. 
100 parts of entirely drj skin give, according to them — 



Table I. 



Tar 



ned with liemlock bark 
" fir bark 
" quebracho bark 
" chestnut bark 
" a la garouille 
" oak bark 



. 2.')5.7 
. 240.1 
. 232.0 
. 219.0 
. 210.0 
206 to 209 



From the results obtained it seems that hemlock and fir 
bark give the best weight, which Miintz and Schon attribute 
to the great quantity of resinous substances absorbed in both 
cases, besides the tannin. They tried to remove the quantity 
of resinous extractive substances contained in leather tanned 
with different tannins by washing with ether and alcohol, and 
found that the quantity extracted amounted — 



Table II. 



In hemlock leather 
" quebracho leather . 
" a la garouille leather 
" oak bark leather . 



to 23 per cent. 



The varying quantities of resinous substances contained in 
the different kinds of leather make, it is said, the difference in 
the solidity, flexibility, etc., of the leather. The larger the 
quantity contained in the leather, the less solid and the more 
brittle it becomes. 

Miintz and Schon make the assertion, which according to our 
opinion is untenable, that leather is a solid combination, and 
consider, according to this, the resinous substances as injurious 
admixtures. The greater the percentage of pure tannin in the 
leather, the better, according to Miintz and Schon, is the leather. 

To form a judgment of the real value of leather tanned with 
different tanning materials, they endeavored to remove all 
resinous substances by extraction and washing with ether and 



> Gerberzeitung, 1881, No. 32. 



128 



THE MANUFACTURE OF LEATHER. 



alcohol, after whicli they dried the leather completely, and 
calculated from this the quantity of tannin absorbed. 
The experiments gave the following results: — 

Table III. 

Hemlock leather contained in 
Sumach leather " " 

Fir leather " " 

Quebracho leather " " 

Chestnut leather 
Oak-bark leather 
Leather in a la garouille . 
Oak bark (3 years in the pit) 

By calculating the above table to 100 parts of skin, we obtain 
the following figures : — 

Table IV. 







Parts of skin. 


Parts tannin. 


. 43.91 


29.23 








45.10 


29.70 








46.70 


42.60 








48.70 


36.70 








52.56 


44.08 








53.36 


41.16 








54.19 


35.13 








56.30 


39.00 



100 parts of skin contain pure tannin — 






As hemlock leather' 


. 64.2 pe 


r cent. 


" sumach leather' .... 


. 61.2 




" fir bark leather ^ .... 


. 90.8 




" quebracho leather . . . 


. 75.3 




" chestnut leather .... 


. 85.2 




" oak-bark leather . . . . 


. 76.9 




" a la garouille^ 


. 64.8 




" oak bark (3 years in the pit) . 


■ . 70.2 





The percentage of glue, tannin, and nitrogen in leather per- 
fectly dry and free from all soluble substances, calculated from 
Table III., should be as follows : — 



Table 



Hemlock 

Sumach . 

Fir bark 

Quebracho 

Chestnut 

Oak 

A la garouille 

Oak (3 years in the pit) 



V. 






Glue. 


Tannin. 


Nitrogen 


60.40 


39.96 


10.88 


60.40 


39.60 


11.00 


52.50 


47.50 


9.56 


57.10 


42.90 


10.40 


53.97 


46.30 


9.79 


55.87 


44.13 


10.24 


60.40 


39.60 


10.94 


58.75 


41.25 


10.65 



1 The figures for hemlock, sumach, and fir bark leather, given in the " Ger- 
berzeitung," are wrong. They should be 66.5 per cent, for hemlock, 65.8 for 
sumach, and 91.2 for fir bark. 

^ A la garouille is probably a variety of leather obtained by mixing the bark 
of Daphne Laureola with Quercus. 



VEG-ETABLE TAJSTNIISTG MATERIALS. 129 

Bj calculating from Table Y. liow many pounds of leather 
free from resin are obtained from 220 lbs. of dry skin, we obtain 
the following figures : — 

Table VI. 

Hemlock 365.2 lbs. 

Quebracho 380.6 " 

Chestnut 407 " 

Oak 374 " 

a la garouille ........ 363 " 

The last table shows that leather tanned with hemlock and a 
la garouille absorbed the least tannin. Leather tanned with hem- 
lock is solid, while that tanned with a la garouille appears soft. 
Miintz and Schon raise the question why equal quantities of 
tannin give such different results, and answer that in tanning with 
hemlock a certain quantity of resinous substances are introduced 
into the interior of the leather which cannot be removed by 
washing with ether and alcohol, and make the fibre brittle. 

Leather tanned with chestnut bark and quebracho furnishes, it 
is claimed, as good a quality as that with oak bark, and at the 
same time a greater increase in weight. As the tannin con- 
tained in these materials costs scarcely half as much as oak 
tannin, the use of chestnut and quebracho would be of advantage. 

Miintz and Schon also draw attention to the fact that leather 
tanned with oak bark kept three years in the pit contained, 
after washing with ether and alcohol, 2 per cent, less tannin 
than that tanned with oak bark two years in the pit. Tiiis 
phenomenon, they say, may possibly be caused by the skins 
differing in their interior condition and possessing a greater or 
smaller absorbing power. 

The question whether a skin by continued remaining in the 
tanning material can absorb larger quantities of tannin, Miintz 
and Schon answer by saying : " The skin does not absorb an 
unlimited quantity of tannin ; there comes the moment of satu- 
ration." In the opinion of these two chemists the quality of the 
leather is not improved by its remaining for a long time in the pit.^ 

^ For portions of the matter in this chapter the author desires to acknowledge 
his indebtedness to the Dictionnaire de Chimie Pure et Appliquee, Wurtz, and 
to Bolley's Technolgie 35 (Bd. vi. 4), Lederbereitung, Heinzerling. 
9 



130 THE MANUFACTUEE OF LEATHEE. 



CHAPTER YII. 

MINEEAL AND AETIFICIALLY PEEPAEED TANNING SUBSTANCES.^ 

Section I. Mineeal Tanning Mateeials. 

The use of mineral tanning materials dates back to very re- 
mote times, since history teaches us that the Saracens used alum 
and aluminium salts for tanning skins. These substances were 
in fact for a long time the only tanning materials employed for 
preparing leather, a series of other mineral substances for tan- 
ning having been only recently introduced as a substitute for 
vegetable substances. 

The principal mineral substances we have to consider are : — 

1. Aliim^ aluminium sulphate^ and aluminium^ acetate, 

2. Ghromates and chromic oxides. 

3. Ferric salts. 

4. Common salt. 

Aluminium Sulphate. 

Neutral aluminium sulphate (AI23SOJ is prepared either by 
treating clay or bauxite with concentrated sulphuric acid, or 
from cryolite. In an anhydrous state it contains 30 per cent, 
of alumina and 70 per cent, of sulphuric acid. With eighteen 
equivalents of water it crystallizes into octahedrons, or at a 
temperature of 32° F. into hexagonal rhombohedrons. Alu- 
minium sulphate is soluble in double its weight of water. 
A solution prepared with the assistance of heat separates, on 
cooling, crystalline lamina of aluminium sulphate (Al23SO^ + 
ISHgO). It is found in commerce in a nearly pure state, the 
best qualities containing only traces of iron, but from 0.5 to 2 

1 Bolley's Teclinologie, 35 (Bd. vi. 4), Lederbereitung, Heiiizerling. 



MINERAL TANNING SUBSTANCES. 131 

per cent, of free sulphuric acid/ which is frequently injurious 
when the salt is to be used for tanning purposes. The presence 
of free sulphuric acid may also be detected by adding to a solu- 
tion of aluminium sulphate some logwood tincture. The solu- 
tion, if free acid is present, will be colored brown-yellow, and 
deep violet, if it is neutral. To make aluminium sulphate con- 
taining free sulphuric acid available for tanning purposes, add 
to a solution of it 1 to 2 per cent, of zinc chips, the solution of 
which will be attended by a violent development of hydrogen. 
By the free sulphuric acid combining with the zinc, zinc sul- 
phate is formed. An excess of zinc is dissolved with formation 
of zinc sulphate and separation of basic sulphate of alumina. 
Instead of zinc chips 1 to 2 per cent, of sodium carbonate may 
be used. 

Aluminium sulphate, known in commerce as concentrated 
alum, is used in tanning as a substitute for alum. The skin 
absorbs, according to Knapp, up to 27 per cent, of it, which is 
removed by washing with water. 

Alum (Al^3SO, + K2S04+24H20), is formed by the combina- 
tion of aluminium sulphate with alkaline sulphates. It is read- 
ily prepared by mixing solutions of the two sulphates. In 
evaporating the fluid, the alum crystallizes out. Potash-alum 
and ammonia-alum dissolve with difficulty, they requiring 18.4 
parts of cold water and 7.5 parts of boiling water, while soda- 
alum dissolves readily. From a hot saturated solution, the 
alum separates in octahedrons, and from alkaline solutions in 
hexadrons. The last variety is called in commerce cubic alum, 
and, being nearly free from iron, is valued more highly than the 
former. Alum has at first a sweetish taste which changes into 
an astringent. By heating it loses graduall}'' its water of crys- 
tallization, becomes anhydrous, and is converted into the so- 
called burned alum. Ferric sulphate, manganous sulphate, and 
chromium sulphate, which are isomorphous with aluminium, 

' To test aluminium sulphate for free sulphuric acid, compound, according 
to Edward Donath, a solution of it at an ordinary temperature with a few drops 
of potassium iodide and potassium bichromate and add a little bisulphate of 
carbon. If free acid is present the iodine is liberated and the bisulphide of 
carbon, on shaking, assumes a beautiful violet color. 



132 THE MANUFACTUKE OF LEATHEE. 

form also double salts when combined with potassium, sodium, 
or ammonium sulphate. The resulting combinations are called 
iron alum, chromium alum, and manganese alum. Instead of 
alumina they contain ferric oxide, chromic oxide or manganic 
oxide. They crystallize in the same form, and contain an equal 
quantity of water of crystallization : — 

Iron alum = Pe,3SO, + K2SO,+ 24Hp. 

Manganese alum = Mn2'3S04 4-K2S04+24H.p. 
: Chromium alum= G^ 3S0, + K,SO, + 24:Rp. 

If several of these alums in solution are present in one fluid, 
the crystals separating from it contain the different bases in 
varying quantity. It is due to this circumstance that alumina 
alum contains frequently iron alum, which it is often impossible 
to remove even by repeated recrystallization. In tawing and 
in mineral tanning potash-alum is principally used. 

For a complete saturation the skin tissue absorbs, according 
to Knapp, 7 to 8 per cent, of alum. 

The tanning properties of alum are principally due to the 
alumina salts it contains. 

In absorption by the skin tissue, the alum, according to 
Knapp and Kaimer, is split, the aluminium sulphate or basic 
aluminium sulphate precipitating upon the fibre, while the 
potassium sulphate remains in the liquid. In the presence of 
common salt in aqueous solution, the alum, according to Knapp, 
is not converted into aluminium chloride and sodium sulphate. 

Iron and chromium alum act upon the skin tissue in the same 
manner as aluminium alum. 

Aluminium acetate (Al26(OC2H30)) is prepared by dissolving 
alumina in acetic acid or compounding lead acetate with 
aluminium sulphate or alum. Heating during the process 
should be avoided. Experiments have lately been made in 
using aluminium acetate in place of aluminium sulphate or alum. 

It does not separate, it is claimed, in a crystalline form in the 
skin, and the leather tanned with it does not become spotted, 
as is frequently the case in tanning with alum. The tanning 
with this salt is more solid than with alum, since the aluminium 
acetate decomposes more or less in the leather by the formation 
of basic salts or free alumina. 



MINERAL TANNIKG SUBSTANCES, 133 

A further advantage claimed for aluminium acetate is the 
absence of free sulphuric acid, which is split off from the 
aluminium sulphate and exerts a very injurious influence upon 

the leather. 

Chromimn Salts. 

Experiments have only been made within the last three or four 
years to use chromates mixed with alumina salts for tanning in 
place of vegetable substances. 

The most important for this method of tanning is the potas- 
sium hichromaie from Avhich all other chromic salts and com- 
pounds of chromium used for technical purposes are derived. 
The salt is chiefly manufactured in three large establishments 
in England, from whence it is sent to all parts of Europe and 
partly to America. It is made by roasting a mixture of finely 
powdered chrome iron-stone with potassium carbonate upon the 
hearth of a reverberatory furnace for several hours with con- 
stant stirring of the mass. The chromium oxide is oxidized to 
chromic acid, the latter combining with the potassium to potas- 
sium chromate. The ferric oxide contained in the chrome iron- 
stone is separated as such. After thorough oxidation the 
roasted mass is lixiviated with water, whereby potassium chro- 
mate, a small excess of potassium carbonate and a few impurities, 
such as potassium silicate, pass into solution. The liquid 
is allowed to clarify by standing, and, after decanting, is evapo- 
rated if necessary, and the neutral potassium chromate con- 
verted into potassium bichromate by adding the required 
quantity of sulphuric acid. The potassium bichromate forms 
large bright garnet-red trichinic crystals. It is soluble with 
difficulty in cold water. 

20 parts of water at 32° F. dissolve 1 part of tlie salt. 
11.8 " " " 50 " " 1 " 

7.65 " " " 68 " " 1 " " 

1.18 " " " 140 " " 1 

Potassium bichromate is very sensitive. With glue, gelatine, 
gum, etc., it forms combinations which, after exposure to light, 
are insoluble in water, its employment in photography for 



134 THE MANUFACTURE OF LEATHER. 

preparing pigment or carbon pictures depending upon this 
property. 

It precipitates itself upon the skin fibre, and partly pene- 
trates it. 

Taken internally it has a poisonous effect like most metallic 
combinations. Placed repeatedly upon excoriated or sore places 
it produces running ulcers, which are, however, soon healed by 
washing with lead vinegar. It colors the sound cuticle yellow 
without destroying it. In pulverizing potassium chromate care 
must be had not to allow the powder to enter the nostrils as it 
produces violent itching and severe spells of sneezing. 

Sodium bichromate is more soluble in cold water than potas- 
sium bichromate, but as it crystallizes with difficulty and does 
not form an article of commerce, it is but little used. 

Calcium bichromate, strontium,' and barium are soluble in 
water, while the neutral chromate of calcium, strontium, and 
barium are soluble with difficulty, the barium salt, which forms 
a well-known art color, being almost insoluble in water. Lead 
salts give with chromic salts insoluble precipitates which are 
used as painters' colors. 

The neutral alkaline chromates are yellow, readily soluble in 
water, and can be used in place of the alkaline bichromates, but 
beino; dearer than the latter offer no advantag-e. 

Chromium alum is the most important of the chromium salts 
thus far introduced in tanning. It is prepared by mixing 
chromium sulphate with alkaline sulphates. It crystallizes from 
the fluid in octahedrons. 

In speaking of alum, it has been mentioned that chromium 
alum acts upon the fibre in the same maimer as aluminium alum, 
but the tanning of leather prepared with aluminium alum being, 
as we will see later on, more perishable on exposure to water than 
that of leather prepared with chromates, the latter are pre- 
ferred. 

Chromic sulphate (CrjoSOJ is obtained by reducing chromic 
acid to chromic oxide, and dissolving in sulphuric acid. It is 
soluble in water, giving to the latter an emerald-green color, 
and has the same tanning effect upon the skin fibre as aluminium 
sulphate. 



MINERAL TANNING SUBSTANCES. 135 

Ferric Salts. 

Tanning with ferric salts was already recommenced in the 
last century by D'Arcet. Bordier, in 1842, obtained a patent for 
tanning by means of ferric sulphate obtained by oxidizing 
ferrous sulphate. 

In modern times Knapp has attempted to reintroduce in 
practice the method of tanning with ferric salts. The ferric 
.sulphate used by him is also prepared by oxidizing ferrous sul- 
phate with nitric acid, the latter being added to a solution of 
the former until eServesceace ceases and all the ferrous oxide 
is converted into ferric oxide. After the cessation of the first 
effervescence ferrous sulphate is again added until effervescence 
ceases, the object of this addition being to reduce any excess of 
nitric acid used. The resulting basic ferric sulphate solution 
should be of a syrupy consistency, and contain chiefly basic ferric 
sulphate and a small excess of ferrous sulphate. 

Prof. Knapp says that only basic ferric sulphate prepared in 
the above manner is adapted for tanning on account of its 
amorphous condition and beautiful brown-yellow color and the 
indecomposableness of its aqueous solution in boiling. The 
commercial basic ferric sulphate, according to Knapp, does not 
give a syrupy solution, is of a much darker color, and the aque- 
ous solution is decomposed by boiling. 

This ferric salt is, according to Knapp, abundantly absorbed 
by the skin tissue and effects a complete tanning of the skin 
fibre. It is claimed that the salt absorbed by the skin cannot 
be removed by treating with water. 

By precipitating a soap solution with the above basic ferric 
sulphate. Prof. Knapp prepares an iron soap which is a com- 
bination of ferric oxide with sebacic acids. This, to complete 
the tanning process, is mechanically fulled into the skin, either 
by itself or mixed with fat solutions or emulsions. 

Comraon Salt 

occupies an important place in tanning. It serves, as has been 
previously mentioned, on the one hand for preserving skins, 
and on the other to accelerate the tanning process in tawing 



136 THE MANUFACTUEE OF LEATHER. 

and mineral tanqing. As regards its occurrence, preparation, 
etc., nothing need be said. 

The salt found in commerce is either rock salt or that ob- 
tained from salt springs or sea-water, the latter being known as 
common salt. Both varieties contain varying quantities of 
admixtures, the principal being the sulphates of magnesia, 
lime, or gypsum, and the chlorides of calcium and magnesium. 
Common salt prepared from sea-water contains the most im- 
purities, the principal being magnesium chloride, magnesium 
sulphate, calcium chloride, etc. The salt obtained from rock 
salt by recrystallization being the purest is especially adapted 
for use in tanning. 

In using common salt in tawing and mineral tanning, admix- 
tures of magnesium chloride and calcium chloride are especially 
injurious as they absorb water from the air, i. e., they are 
hygroscopic. 

When salt containing these admixtures is used for tanning 
the leather produced with it absorbs water from the air and 
becomes moist. 

Section II. Artificially Prepared Tanning Substances. 

Many attempts have been made to substitute artificial tan- 
ning substances for those of a vegetable or mineral origin 
occurring iti nature. Although they have thus far not been 
introduced in practice we will briefly describe the manner of 
preparing them. 

Jennings patented in 1848 an artificial tanning material pre- 
pared in the following manner: Dense black peat is thoroughly 
dried and pulverized, and treated with 10 to 20 per cent, of 
concentrated nitric acid gradually added. The mass becomes 
hot in a short time and evolves yellow-red vapors of nitrous 
acid, the escape of which is partly prevented by covering the 
apparatus. When the action of the nitric acid has ceased, six 
to ten times the quantity of water of acid used is added, and 
the whole heated for a few hours with frequent stirring, the 
object of heating being to accomplish the solution of the tannin 
formed by the action of nitric acid. In order to use peat re- 



MINERAL TANNING SUBSTANCES. 137 

cently cut, it must be heated with steam to 176° to 212° F. 
before treating with nitric acid. The tannin dissolved in the 
fluid is freed from the coloring matter bj adding a few per 
cent, of stannous chloride and boiling for a few minutes. The 
coloring matter is precipitated, after which the clear super- 
natant fluid is decanted off. 

Aluminium sulphate and common salt can also be used for 
precipitating the coloring matter. 

The skins to be tanned are immersed for a few hours in the 
tanning solution and frequently moved, and then placed for a 
few hours in an alkaline carbonate solution and also frequently 
moved, when they are replaced in the tannin solution, next in 
the alkaline solution, and so on until they are completely 
tanned. 

Sky manufactures a similar tanning material (Wagner's 
Jahresberichte, 1867, 666). 

Lees patented in 1858 the following method of preparing 
artificial tannin. The heavy oils obtained in the dry distillation 
of coal or bituminous shale are treated with concentrated sul- 
phuric acid until a carbonaceous, resinous mass is obtained. 
To accelerate the action of the sulphuric acid upon the oily 
mass, the mixture of sulphuric acid and oil is indirectly heated 
with steam. The resulting black, pitchy mass is boiled with 
nitric acid and then compounded with ammonia, or ammoniacal 
liquor or some other alkali, until the acid is neutralized. An 
excess of alkali must be avoided, as it exerts a dissolving effect 
upon the pitchy mass. Lees calls the resulting product mine- 
ral tan. For tanning it is dissolved in water, and the skins are 
allowed to remain in intimate contact with the solution for some 
time, after which they are finished in a solution of alum or 
other salts. 

Another kind of artificial tannin is formed by heating a solu- 
tion of resins and camphor with sulphuric acid.^ After some 
time the mass becomes black. By adding water a black pow- 
der is separated, the alcoholic extract of which on being evapo- 
rated leaves behind the artificial tannin. The chemical nature 

' Muspratt, iii. 106. 



138 THE MANUFACTURE OF LEATHER. 

of the tannins obtained by these processes can only be conjec- 
tured, since they have not been scientifically examined. 

The tannins obtained by treating peat, brown coal, coal, etc., 
with nitric acid are very likely nitro-combinations of the aro- 
matic series and possibly closely related to picric acid, for it is 
well known that by the action of nitric acid upon a series of 
organic substances yellow nitro-combinations are formed which 
are frequently considered as picric acid. Picric acid^ in aqueous 
or alcoholic solution converts the skin into leather, but is not 
used in practice on account of its high price. 

The tannins obtained by the action of sulphuric acid upon 
resins and. camphor may possibly be sulpho-combinations of 
organic bodies, such as are frequently produced by sulphuric acid. 



CHAPTER VIII. 

CHEMICAL EXAMINATION OF VEGETABLE TANNING MATERIALS. 

Most tanners determine, even at the present time, as has been 
done for hundreds of years, the quality of the tanning material 
by its appearance, taste, and odor. While with some experience 
it may be possible by these means to distinguish good bark 
from a bad article, they offer no guide for the finer distinctions 
in value. 

That an absolutely accurate method of determining the tannic 
acid in the various tanning materials is wanting even at the 
present day, may be explained by the fact that, with the excep- 
tion of gallotannic acid, we know next to nothing, in a chemical 
respect, of the different tannins. 

As regards the properties and mode of distinguishing the 
tannins occurring in the various vegetable tanning materials, 
we refer to what has been stated in Chapter YI. 

• Picric acid, C6H2(N02)3HO, is obtained by the action of nitric acid upon phe- 
nol, indigo, benzole, silk, wool, resins, etc. It forms pale yellow crystalline 
lamina, and is soluble with difficulty in water, but readily in ether or spirit of 
wine. 



EXAMINATION OF VEGETABLE TANNING MATERIALS. 139 

Method of Determining the Tannic Acid. 

The quantity of tanning matters contained in the different 
astringent products used in industry has a valuable practical 
importance and a large number of methods have been proposed 
to reach this result in the most rapid and accurate way possible. 

The areometer (tan-meter) is an instrument which has been 
used for some time to obtain an idea as to the strength of the tann- 
ing liquors, and the percentage of the bark. The percentage of 
tannic acid is estimated from the greater or smaller specific 
gravity of the aqueous solution of a determined quantity of tan- 
ning material. The richer the aqueous solution in tannic acid, 
the higher its specific gravity. This method furnishes inaccu- 
rate results, since the bark, according to its age and the soil 
upon which it is grown, contains varying quantities of other 
substances soluble in water, which affect the specific gravity of 
an aqueous solution. The following substances occur, according 
to Gerber, in an aqueous solution of the inside layer of oak 
bark: — 



Tannin , 8.05 

Gallic acid 1.59 

Sugar 

Extractive substances ^ ....... 8.33 

Malic acid 
Rosin 



•1 



6.31 
Fat > 

Gum 5.60 

Quercus red . . . . . . . . .2.34 

Pectic acid 6.77 

Davy first indicated a volumetric method founded on the 
precipitation of the gelatine with the tannin. To the aqueous 
extract of a known weight of astringent matter is added an ex- 
cess of a solution of gelatine or isinglass (1 part of isinglass for 
6 parts of the astringent solution). The precipitate gathered 
on the filter, washed, dried, and weighed, represents -^-^ of its 
weight in tannin. The results thus obtained are very weak, as 
the precipitate of tannate of gelatine always passes partially 
through the filter. According to Mliller, this inconvenience 
may be obviated by the use of a solution of gelatine containing 
some alum. In that case the precipitate separates completely, 



140 



THE MANUFACTURE OF LEATHER. 



and Fehberg has even been able to found, on the use of alumi- 
nated gelatine, a process of volumetric denomination. The nor- 
mal solution contains 10 grms. of air-dried gelatine per litre 
and 3 grras. of alum. This liquor is titrated by means of a 
solution of pure tannin containing 2 grms. per litre. 

It is evident that this process can only be applied to the tan- 
nins which precipitate gelatine ; but, as they are also those that 
enter into the composition of tanning matters, this restriction 
does not diminish the value of the process. One can judge of 
the termination of the reaction when a small quantity, taken 
for trial from the clear liquor and put in a testing vessel, does 
not sensibly become troubled by the gelatine or tannin. 

Miintz and Rampercher^ filter the tanning liquor under pres- 
sure through a moistened skin from which the hair has been 
removed, and weighed while dry. 

By drying the skin later on at 212° F. they learn from the 
increase in weight the amount of tannic acid contained in the 
solution. They have constructed a small apparatus shown in 
Fig. 6. 

The lower part serves as a support for a piece of prepared 
skin. When the apparatus is to be 
used, the upper part, which is provided 
with a long arm, is connected with 
the lower by means of clamp screws- 
The space between the piece of skin 
and the helmet of vulcanized rubber is 
sufficiently large to hold 100 c,c. of 
tanning liquor, the specific gravity of 
which has been previously determined 
by the areometer. The brass cover on 
the side is then screwed down tightly, 
and the liquor forced down upon the 
skin, which absorbs all the tannic acid, 
by the pressure of the perpendicular 
screw upon the rubber helmet. The 
water and other substances of the solu- 



Fis. 6. 




1 Comptes rendus, Ixxix. 380, and Ding. Polyt. Journ., ccxiv. 74. 



EXAMINATION OF VEGETABLE TANNING MATERIALS. 141 

tion run off into a glass vessel, and are tested as to their specific 
gravity with the areometer, the percentage of tannic acid being 
shown by the difference between the two gravities. 

This apparatus is said to answer the purpose very well. It 
recommends itself at any rate by its simplicity and the quick- 
ness with which a determination of the tannic acid can be exe- 
cuted. 

Fleck and Wolf's^ method is based upon the precipitation of 
the tannin with a solution of cupric acetate, 100 parts of cupric 
oxide= 130.4 of tannic acid (WolP). 

Persoz's method. — Risle Bennat^ describes a process by Persoz, 
according to which the tannic acid is precipitated with stannous 
chloride solution, and its percentage estimated by measuring 
and comparing the precipitate, several measuring cylinders 
graduated into y^ of parts being used for the purpose, A 
solution of tannic acid of a determined percentage is prepared 
by dissolving 10 grms. of dry pure gallotannic acid in water and 
diluting the solution to one litre. The stannous chloride 
solution is prepared by dissolving 8 grms, of stannous chloride 
and 2 grms. of sal ammoniac in 1000 c.c. of water. To deter- 
mine the tannic acid, for instance in barks, 10 grms. of the 
latter are boiled in half a litre of water for half an hour. The 
decoction is filtered and the residue washed out with sufficient 
hot water to make the total quantity of the fluid equal to 1 litre. 
100 c.c. of this solution are brought into the measuring cylin- 
der by means of a pipette and slowly compounded with 100 c.c, 
of the stannous chloride solution. After settling for ten or 
twelve hours the amount of precipitate is read off" from the scale 
of the cylinder. 

A comparative experiment being made at the same time 
with the normal solution mentioned above, by adding to 100 

' Wagner, Jaliresbericlite, 1861, 625, 

2 According to Pavesi aud Rotondi 145 parts of tannic acid (Berichte der 
deutsch, chera. Ges, 1874, 590), Schiff explains these differences by the 
use of tannic acids of varying purity. By using pure tannic acid (t. e., digallic 
acid Cj^HigOg) 100 parts of cupric oxide would, according to »ScA;/7', correspond to 
136 parts of tannic acid. 

3 Zeitschr. f. analyt. Chemie, 1863, 287. 



142 THE MANUFACTUKE OF LEATHEE. 

c.c. of it, a like quantity of stannous chloride solution, the per- 
centage of tannic acid can be readily determined from the 
relative volumes of the two precipitates. If, for instance, 50 
c.c. of precipitate are obtained with the normal tannic acid, and 
only 7 c.c. with tiie test fluid, the percentage of this substance, 

7 X 100 

if 10 sfrms. were contained in 1 litre, would be = 14 per 

, ' 50 ^ 

cent. 

Grauhe advises especial care that the difference in the volumes 
of the precipitates is not too great. The extracts of the tanning 
materials should, if necessary, be concentrated, or the test acid 
diluted. The fluids must, of course, stand at an equal height 
in the cylinders. 

To enable persons not possessing graduated cylinders to avail 
themselves of this method, Risle Bennat proposes the determi- 
nation of the precipitate, previously washed out and dried hy 
gravimetric analysis. By heating the precipitate with ammo- 
nium nitrate pure stannic oxide is obtained. The percentage of 
tannic acid is found by subtracting the amount of stannous 
oxide calculated from the stannic oxide (100 SnOg correspond 
to 89.33 SnO) from the previously found weight of the pre- 
cipitate of stannous tannate. This method may be recommended 
for technical purposes, especially in cases where gallic aciel 
occurs with tannic acid. 

Wildenstein^s^ colorimetric method is based upon the coloring 
which strips of paper saturated with ferric citrate assume when 
dipped in a fluid containing tannic acid. Wildenstein claims 
that the percentage of tannic acid can be estimated by com- 
paring the depth of the coloring with an empirically obtained 
color-scale. 

Fehliny's method^ modified hy G. Muller? — This is based upon 
the precipitation of the tannic acid with titrated aluminated 
solution of glue. To prepare the glue solution 10 grms. of white 
bone glue are soaked in distilled water, and, after swelling, 
dissolved by moderate heating, 25 grms. of alum are then added 

' Zeitschr. fur aiialyt. Chemie, 1863, 137. 

2 Liebig and Kopp Jahresberichte, 1853, 683. 

3 Ding. Polyt. Journ., I. 51 to 69. 



EXAMIXATIOX OF VEGETABLE TANNING MATERIALS. 143 

and the whole diluted to 1 litre. The titre of the glue solution 
undergoing quick alteration, it must every time be re-established 
to the normal tannin solution. 0.2 grm. of dry gallotannic acid 
requires for complete precipitation 22.7 c.c, 1 c.c. of this glue 
solution corresponding consequently to 0.0088 grm. of tannic 
acid. 5 grms. of the bark to be tested are boiled three or four 
times in 50-60 c.c. The resulting solution is filtered and 
diluted with water to 500 c.c. To 50 or 100 c.c. of this 
solution, glue solution is added from a burette, with constant 
stirring, until all the tannic acid is precipitated. The stirring 
is done, according to Hallwachs, with a glass tube open on 
both ends, with which, in the same manner as with a pipette, a 
sample is taken from the supernatant fluid and placed upon a 
small filter. To the filtered sample a drop of glue solution is 
added by allowing it to remain suspended in the upper part of 
the tube, which is held obliquely, and then rinsing it carefully 
with distilled water into the sample fluid. If the latter remains 
clear, the reaction is finished, but if it becomes turbid, the 
filtered sample and the filter are returned to the test fluid and 
more glue solution added to the latter from a burette. This is 
carefully continued until a small sample gives no turbidity with 
tannic acid nor with glue solution. Should turbidity be caused 
by tannic acid, an excess of glue solution has been added, neces- 
sitating a repetition of the test. 

Satisfactory results are, according to Gauhe* and Hallwachs,^ 
obtained by this method, but, on account of the tedious manner 
of execution, it is not suitable for easily making many determin- 
ations of tannic acid. 

In place of white glue, Lippowitz^ uses isinglass for precipitat- 
ing the tannic acid. According to his statement 1 grm. of 
insinglass dried over sulphuric acid precipitates exactly 0.75 
grm. of tannic acid, a solution of 1.333 grms. of isinglass sufficing 
consequently for the precipitation of 1 grm. of tannic acid. 

Carpene-Barhieri's method is based upon the precipitation of 
the tannic acid with an ammoniacal solution of zinc acetate. 

' Zeitschr. f. analyt. Chemie. 

2 Gewerbeblatt f. d. Grosshergogtli, Hessen, 1845, 51 w. 52. 

^ Wagner .Jahresberichte, 1861, 624. 



144: 



THE MANUFACTUEE OF LEATHER. 



One-tliird of the precipitated fluid is evaporated by boiling. 
The precipitate obtained is filtered, washed with hot water, and 
dissolved in dilute sulphuric acid. The insoluble substances 
are separated from the solution by filtering, and the filtrate 
tritrated with solution of potassium manganate. Kathreimer,-^ 
on subjecting this method to a closer examination, found the 
results obtained by it to be inaccurate. 

Gerland's me^/iorZ^ is based upon the precipitation of the tannic 
acid with tritrated solution of tartar emetic. Hallwachs^ and 
Koller,^ who have already had control of this method, are of 
the opinion that an accurate determination of the tannic acid 
can in no case be attained with Gerland's method. 

Jeans' s^ method of determination is based upon the action of 
tannic acid and gallic acid to fix, in the 
presence of sodium carbonate, a propor- 
tional quantity of iodine. The extractive 
substances of oak bark, it is claimed, exert 
no disturbing influence whatever. If, be- 
sides tannic acid, gallic acid is present, two 
tritrations are required, one direct and the 
other indirect, after the tannic acid has 
been removed by means of animal skin or 
gelatine. 

Kathreiner, who tested this method, con- 
siders it as very tedious and requiring too 
much time. A further evil is the quick 
alteration of the titre of the iodine solution. 
K. Ilammer^s method^ is based upon prin- 
ciples coming closest to the true conditions in tanning, and 
furnishes, if in any way accurately executed, good corresponding 
results. Hammer determines the specific gravity of the fluid 
containing the tannic acid by means of a picnometer (Fig. 7) or, 



Fi>. 7. 



Ill 




PiciK'iufter. 



1 Dingl. Polyt. Journal, ccxxvii. 489. 

2 Chem, News, 1863, 54, Zeitschr. f. analyt. Chemie, 1863, 419. 

3 Dingl. Polyt. Journ., clxxx. 50. 

* Neiies Jalirbncli fiir Pharmacia, xxv. 206. 

6 Bei-icht d. deutscli. Chem. Gesellsch. 1877, 730. 

" Journal f. prakt. Chemie, Ixxxi. 156. 



EXAMINATIOISr OF VEGETABLE TANNING- MATERIALS. 145 

an areometer, wliich indicates the specific gravity to 1.0409. 
Next he precipitates the tannic acid from the fluid with especi- 
ally prepared animal skin, and determines the specific gravity 
after precipitation. The difference in the two specific gravities 
is in proportion to the percentage of tannic acid. 

To facilitate the calculation of the latter, the following table 
is used from which the relation between the specific gravity 
and the percentage of tannic acid of varying concentration can 
be seen. 



Per cent, of 


Specific gravity 


Per cent, of 


Specific gravity 


Per cent, of 


Specific gravity 


tannic acid. 


at 59° F. 


tannic acid. 


at 59° F. 


tannic acid. 


at 09° F. 


0.0 


1.0000 


1.7 


1.0068 


3.4 


1.0139 


0.1 


1.0004 


1.8 


1.0072 


3.5 


1.0140 


0.2 


1.0008 


1.9 


1.0076 


3.6 


1.0144 


0.3 


1.0012 


2.0 


1.0080 


3.7 


1.0148 . 


0.4 


1.0016 


2.1 


1.00S4 


3.8 


1.0152 


0.5 


1.0020 


2.2 


1.0088 


3.9 


1.0156 


0.6 


1.0024 


2.3 


1.0092 


4.0 


1.0160 


0.7 


1.0028 


2.4 


1.0096 


4.1 


1.0164 


. 0.8 


1.0032 


2.5 


1.0100 


4.2 


1.0168 


0.9 


1.0036 


2.6 


1.0104 


4.3 


1.0172 


1.0 


1.0040 


2.7 


1.0108 


4.4 


1.0176 


1.1 


1.0044 


2.8 


1.0112 


4.5 


1,0] 80 


1.2 


1.0048 


2.9 


1.0116 


4.6 


1.0186 


1.3 


1.0052 


3.0 


1.0120 


4.7 


1.0190 


1.4 


1.0056 


3.1 


1.0124 


4.8 


1.0194 


1.5 


1.0060 


3.2 


1.0128 


4.9 


1.0198 


1.6 


1.0064 


3.3 


1.0132 


5.0 


1.0202 



Franz Schulze^ has modified this method by adding 10 grms. 
of white glue to a concentrated solution of sal ammoniac and 
diluting to 1 litre by a further addition of pure solution of sal 
ammoniac. 10 grms. of gallotannic acid are, in the same man- 
ner, dissolved in concentrated sal ammoniac and the solution 
diluted to 1 litre. The addition of sal ammoniac is claimed to 
facilitate the settling of the precipitate. The bark extract is 
saturated with sal ammoniac, and, after compounding with a 
teaspoonful of white sand or glass powder, the glue solution is 
gradually added, with constant stirring, until the formation of 
the precipitate is more and more plainly observed. The nearer 
the point of saturation is approached, the quicker, by allowing 



' Dingl. Polyt. Jour, clxxxii. 155, bis 158. 



10 



146 THE MANUFACTURE OF LEATHER. 

the mixture to stand quietly, is tlie sediment shown, until the 
precipitation takes place inside of half a minute, and the fluid 
appears clear. 

Salzer,^ who tested Schulze's method, remarks that with some 
experience it is easily and quickl}?- executed, but as the precipi- 
tate, though separating itself readily, floats on top if the fluid 
contains too much sal ammoniac, he recommends the use of a 
less concentrated solution of sal ammoniac. 

In executing Hammer's method, it must first of all be ob- 
served, that the tannic acid to be determined, is obtained frbm 
the substance in as concentrated a solution as possible, because 
if the difference in the specific gravities is greater before and 
after precipitation, the error of observation is smaller. 20-30 
grms. of the substance are boiled with 50-60 c.c. of water 
for 30 to 40 minutes, the water lost by evaporation being con- 
stantly replenished, and then completely exhausted with five to 
six times the quantity of hot water, and filtered. The clear fil- 
trate is weighed and reduced to a round number of 350 to 400 
grms. After cooling, the specific gravity of the fluid is deter- 
mined either with the picnometer or the areometer, all precau- 
tions required for such operations being of course used. 

Sufficient test fluid to fill the picnometer or a cylinder in 
which the areometer is to be immersed is weighed off in a 
matrass which may be either dry or previously rinsed out with 
fluid containing tannic acid, and then four times the quantity 
of tannic acid, found by a preliminary determination from the 
specific gravity, of unhaired animal skin is added. The latter 
is best prepared in the following manner : A piece of skin pre- 
pared for tanning by freeing it from hair, lime, etc., is placed in 
running water for several hours, then stretched upon a clean 
board, and after drying converted into powder with a coarse 
rasp. 

The powder can be kept in a hermetically closed flask for 
some time. Before use it is soaked in cold water for a short 
while, then thoroughly pressed out in a linen cloth between the 
hands to prevent the adhering water from changing the specific 

^ Zeitschr. f. analyt. Chemie, 1868, 70. 



EXAMINATION OF VEGETABLE TANNING MATERIALS. 147 

gravity of tlie fluid containing tannic acid. After adding the 
skin powder to the fluid, the matrass is closed and shaken for 
some time. 

An approximate weighing of the fluid and skin powder only 
is required. After the precipitate has settled, the supernatant 
fluid is poured off" through a fine cloth either directly into the 
measuring cylinder or into the picnometer, and the specific 
gravity determined. 

Special areometers have been constructed for practical use, 
which show directly the quantity of tannic acid by the differ- 
ence in the specific gravity. The graduation of this areometer 
is according to degrees or per cents. Suppose a solution of tan- 
ning material shows before precipitation 5.5 per cent, and after 
precipitation 1.5 per cent., the amount of tannin would be 4 per 
cent. 

But if the percentage of tannin is to be calculated from the 
specific gravity found by means of the areometer or picnometer, 
the following example may serve for an illustration : — 

30 grms. of bark have been exhausted with 850 grms. of 
water. The specific gravity which was 1.01 at 59° F., indicated 
2.5 per cent, of tannin. After precipitation with skin powder 
and filtering, the specific gravity was 1.006=1.5 per cent, of 
tannin. The difference between the two determinations beiuo; 
1 per cent., the fluid is a 1 per cent, one, and the 350 grms. con- 
sumed contained 3.5 grms. of tannin. As the latter were con- 
tained in 30 grms. of bark, the calculation (30 : 3.5 : : 100 : x) 
gives 11.66 per cent, as the amount of tannin contained in the 
bark. 

Mittenzioei^ and TerreiVs^ method is based upon the well- 
known property of tannic acid and allied substances to absorb, 
when in alkaline solution, oxygen. The quantity of tannic acid 
is calculated from the amount of oxygen absorbed in the pres- 
ence of potash, and they use for the determination a graduated 
testing tube of special form and arrangement. 



1 Journ. f. prakt. Chemie, Ixi. 61. 

2 Coinptes rendus, Ixxviii. 790. 



14:8 



THE MANUFACTUKE. OF LEATHEE. 



Fi?. 8. 



This method, which, according to the statements of the 
authors, is also adapted to the determination of ferrous oxide, 
manganesous oxide, and indigo, is executed 
in the following manner : — 

The air in a flask having a capacity of 1 
litre (Fig. 8) communicates with the atmos- 
phere by means of the bent glass tubes h and 
c, the upper part of the latter narrowing to 
1.5 to 1 millimeter. The connection of Jhe 
two glass tubes is effected by means of a 
moderately long rubber tube provided with 
a compression stopcock. The tubes pass 
into the flask through a hole in the cork, or, 
better through a rubber stopper. Before 
commencing the operation, the air in the 
flask and all fluids to be used should have 
the same temperature as the working room, one of 59° F. being 
the best. The flask A is then filled with 200 c.c. of 8 to 5 per 
cent, solution of potash or soda lye to which is added 1 grm. of 
tannic acid wrapped lightly in paper. After placing the cork 
firmly in the flask, the compression stopcock is opened for a 
moment in order to place the inclosed air under the pressure of 
the atmosphere, the absorption of oxygen being facilitated by 
frequent shaking. An increase in the temperature of the flask 




Fiff. 9. 




is prevented by wrapping a cloth around the hand. After 
shaking the flask several times, water is drawn in through, the 
aperture c?, of the pipe c, from a weighed beaker glass />, by 
opening the compression stopcock / (Fig. 9). 



examhstatiojst of vegetable tanning materials. 149 

The experiment is finished when, after frequent shaking, no 
more absorption takes place. The grammes of water entering the 
flask from the beaker glass which are found from the difference 
in the weight of the beaker glass before and after the operation, 
indicate the number of cubic centimeters of oxygen absorbed, 
which can be readily reduced to a temperature of 32° F. and 
29.922 inches pressure by the well-known formula. 1 grm. of 
tannic acid and 1 grm. of gallic acid absorb, according to Mit- 
tenzwei, 175 c.c. of oxygen, and, according to Terrell, 200 c.c. 
The great difference in these statements, which would make 
this method, otherwise simple and practical, appear inaccurate, 
is very likely due to the different degrees of concentration of 
the alkaline solutions used, as, according to Mittenzwei, 1 grm. 
of tannic acid in 200 c.c. of potash lye of 35 per cent. KOH, 
absorbed, after continued and rigorous shaking, not more than 
22 c.c. of oxygen. This interesting fact deserves closer inves- 
tigation. 

We will further mention that Terrell, in modifying Mittenz- 
wei's method, and using a concentrated 30 per cent, potash lye, 
in place of dilute solution, found that, by extending the dura- 
tion of the action to twenty-four hours, a larger quantity of 
oxygen was absorbed. 

The calculation of the result is very simple. Suppose 140 
grms. of water have been drawn from the beaker glass into the 
flask, they would correspond to 140 c.c. of oxygen. If a more 
accurate result is desired, this volume is reduced to 32° F., and 
29.922 inches pressure with a simultaneous consideration of the 
tension of steam. 

As, according to Mittenzwei, 175 c.c. of oxygen correspond 
to 1 grm. of tannic acid, the amount of tannic acid found by 
calculation (175 : 140 : : 1 : x) will be 0.8 grm. 

In the presence of tannic and gallic acid, Mittenzwei pro- 
poses the precipitation of the first by depilated skin, to place 
the filtrate in the absorbing flask, to add 3 to 4 per cent, of 
potassium or sodium hydrate, and determine the gallic acid in 
the above manner. If the total quantity by absorption of oxy- 
gen in the flask has been previously determined, the percentage 



150 THE MANUFACTURE OF LEATHER. 

of tannic acid is found from the difference in tlie two determina- 
tions. 

It is recommended to make a preliminary experiment in or- 
der "to approximately calculate from it the quantity of substance 
fixed by 175 c.c. of oxygen. It is an open question whether 
the tannins derived from various substances absorb, under 
equal conditions, a like quantity of oxygen. 

As the property of absorbing oxygen in alkaline solution is 
possessed by tannic acid in common with a series of other Qr- 
ganic substances, it still remains to be determined, whether 
such substances as pectine, etc., which generally accompany tan- 
nic acid, would not also become more highly oxidized, and the 
found percentage of tannic acid, in consequence of this, be too 
high. 

Hallwachs, who compared Mittenzwei's with various other 
methods, found at least that the result obtained by it was more 
than 1 per cent, too high. 

Terrell, who used the same process, found, as previously 
mentioned, that 0.1 grm. of tannic acid absorbs 22 c.c. of oxy- 
gen. The absorption is complete only after twenty-four hours. 
Terrell executes the experiment in a tube divided into cubic 
centimeters, and provided on one end with a glass faucet and 
hermetically closed on the other end with a glass stopper 0.1-0.2 
grm. of the substance to be examined, and 20 c.c. of a 30 per 
cent, potash lye are placed in a tube, and allowed to react for 
twenty-four hours, with frequent shaking. The tube is then 
opened in a beaker glass filled with water, and the absorption 
taking place observed, the percentage of tannic acid being cal- 
culated from the latter. 

Although this method is rendered inconvenient by the neces- 
sity of taking into consideration the conditions of temperature 
and pressure of air, it deserves to be thoroughly tested to make 
it available in the future. 

Grassi's Metliod. — Grassi^ proposes the precipitation of the 
tannic acid with barium hydrate as barium tannate, to separate 
from the latter the barium by means of sulphuric acid, and to 

' Bertclit der deutscli. cliem. Gesellsch. 1875, 254. 



EXAMINATION OF VEGETABLE TANNING MATERIALS. 151 

determine the tannic acid by titration with potassium perman- 
ganate. This method requires to be further perfected. 

Wagner^s Method.— Wagner^ first divided, as previously 
mentioned, the various tannins into pathological and physical. 
The latter only being of value to the tanner, he endeavored to 
determine them by a simple method. As in his opinion the 
pathological tannic acid or tannin obtained from gall-nuts, 
which was formerly employed for making the titre, could not 
be used as a basis for the determination of the physiological 
tannic acid, he endeavored first to determine the atomic weight 
of the latter. He chose for this purpose tannic acid obtained by 
boiling the inside layer of oak bark. He precipitated the bark 
extract with sulphate of cinchonin, converted the resulting pre- 
cipitate into tannate of lead by boiling with acetate of lead, and 
decomposed the tannate of lead into tannic acid and lead mono- 
sulphide b}^ means of sulphuretted hydrogen. The tannic acid 
contained in the solution was once more precipitated with cincho- 
nin solution, the precipitate washed and dried, and, after weigh- 
ing, suspended in water, and compounded with potassium per- 
manganate, added drop by drop, until the tannic acid was entirely 
destroyed. To this fluid was then added sulphuric acid, in 
order to convert the cinchonin contained in it, into sulphate of 
cinchonin. The latter was dried at 248° F., and weighed as 
neutral sulphate of cinchonin. By assuming the atomic weight 
of cinchonin as 308, Wagner found, that of quercitannic acid as 
813. For the precipitation of 1 grm. of quercitannic acid, 
0.3715 grm. of cinchonin, equal to 0.4523 grm. of sulphate of 
cinchonin, is required. Besides cinchonin, which is chosen as 
being considerably cheaper, quinine, morphine, strychnine, etc., 
may be used for the purpose. Sulphate of cinchonin purified 
by recrystallization is of a constant composition. An admix- 
ture of cinchonidine, both bases being isomeric, is not inju- 
rious. 

To execute the determination, Wagner dissolves 4.523 grms. 
of sulphate of cinchonin in 1 litre of water. As an indicator he 
uses acetate of roseaniline, of which he adds 0.08-0.1 grm. to the 

' Dingl. Polyt, Jour., clsxxiii, 227. 



152 THE MANUFACTURE OF LEATHER. 

above fluid. In connection with the cinchonin solution, the 
aniline red indicates the end of the precipitation of tannic acid 
by coloring the fluid beneath the precipitate red. 0.061 cubic 
inch of the mentioned cinchonin solution is equal to 0.1 grm. 
of tannic acid. It is of advantage to add before the experiment 
0.5 grm. of sulphuric acid, as this accelerates the settling, and 
makes the precipitate less soluble. Wagner used for his deter- 
minations 10 grms. of the substance containing tannic acid, and 
after boiling with water for some time and filtering, diluted the 
obtained solution to 500 c.c. To 50 c.c. of this solution, 
which were equal to 1 grm. of the substance used, he added 
cinchonin solution from a burette, until the fluid above the 
flaky precipitate ceased to be turbid, and assumed a slightly 
reddish color. 

Although with some experience a conclusion as to the com- 
pleteness of the precipitation can be drawn from the condition 
of the precipitate, and the facility with which it settles, it is 
always best to make controlling experiments. The precipitates 
consisting of tannate of cinchonin are collected, and, after a con- 
siderable supply of them has been obtained, boiled with acetate 
of lead and water, until the reddish coloring of the precipitate 
is changed into a brown, and all the cinchonin has passed into 
solution. The excess of lead is separated from the hot filtered 
solution by means of sulphuric acid, and neutral sulphate of 
cinchonin obtained from the fluid freed of lead sulphate by 
evaporation with an addition of sulphuric acid. 

Blichner,^ who subjected Wagner's method to a thorough 
test, remarks that in order to observe* the approach of the final 
reaction by the quick or slow settling of the precipitate, the 
manner of shaking the bottle exerts a material influence. He 
recommends it to be done with a horizontal, circular motion, 
which will effect the settling of the precipitate in five to eight 
minutes, so that the supernatant fluid will be perfectly clear, 
and can be readily judged as regards coloring. Many experi- 
ments have convinced Biichner of the futility of adding less 
than 0.2-0.3 c.c. of cinchonin solution, since 0.1 c.c. of it ex- 

^ Dingl. Polyt. Jour, clxxxiv. 334. 



EXAMINATIOX OF VEGETABLE TANNIJSTG MATERIALS, 153 

erts no perceptible effect upon the final reaction. In case the 
precipitate settles with difficulty, which is frequently the case 
with barks containing a high percentage of tannin, several sam- 
ples are taken from one and the same decoction. To one of 
the samples 2 c,c, are added and allowed to settle quietly, to 
another one 4 c.c, to a third 6 cc, to a fourth 8 c.c, and ob- 
served after some time to see which sample is precipitated. If 
the third sample, which contained only 6 c.c, is not ready, 
while in the fourth, which contained 8 cc, the final reaction 
has been exceeded, only 7 c.c, are added to a fifth sample. 
The determination can be quickly and accurately executed in 
this manner. As regards Biichner's experiments in order to 
study the behavior of sulphate of cinchonin and other sub- 
stances, used for the determination of tannic acid towards pec- 
tine substances, which generally accompany tannic acid, we refer 
the reader to the original essay, but will remark here, that 
according to these experiments, sulphate of cinchonin, solutions 
of glue, and alum produced by themselves no precipitation of 
pectine substances, while the results obtained according to the 
Persoz and Fehling-Mliller method, were more or less too 
high. 

Neubauer, who in his treatise, " Die Schalung der Eichen- 
rinden"^ (Wiesbaden, W. Kreidel), criticizes Wagner's method 
of determining the atomic weight of quercitannic acid, shows 
the incorrectness of the atomic weight found by Wagner, and 
comes to the conclusion that Wagner's method is not available 
in its present form, as the results obtained by it are too low. 

Clark has modified Wagner's method as follows : To a so- 
lution of tanning material is added an excess of solution of 
sulphate of cinchonin (•i.523 grms.) of the salt, 0.5 grm. of 
sulphuric acid, and 1 litre of water. The solution is filtered, 
washed out, and the residue determined with mercuric iodide 
(13.546 grms.) of mercuric chloride, and 49.8 grms. of potassium 
iodide to 1 litre of water. The amount of tannic acid is calcu- 
lated from the difference bv subtractins; from the cinchonin solu- 
tion first used the quantity added in excess which is found by 

. ' " Stripping of Oak Barks." 



154 THE MANUFACTUEE OF LEATHER, 

retitration with solution of mercuric iodide. 1 c.c. of cinchonin 
solution precipitates 0.01 grm. of tannic acid, and 1 c.c. of so- 
lution of mercuric iodide is required to precipitate the cincho- 
nin from 2.74 c.c. of cinchonin solution. This process cannot 
be recommended on account of the final reaction, as in all pre- 
cipitating, analyses being very uncertain. 

LoewenthaVs Method modified hy Neuhauer} — This is the most 
important of all the methods for determining tannic acid, as, 
when correctly executed, it furnishes results which always agre§, 
and besides the process is easy and sure. It has been known for 
a long time that tannic acid in aqueous solution is readily oxi- 
dized by substances yielding up oxygen, as for instance, by 
solution of calcium chloride, or alkaline solution of potassium 
ferridcyanide, and especially by potassium permanganate. 

A dilute solution of the latter was first used for precipitating 
tannic acid by Monier,^ who added it until the fluid assumed a 
red color by an excess of it. 

LoewenthaP showed that the tannic acid in the presence of 
indigo solution is so completely destroyed, that with the dis- 
appearance of the blue color, the last trace of the tannic acid 
present is also decomposed, this being a sure and easy guide for 
the determination of the final point of reaction. 
For the execution of the process are required : — 
1. An indigo solution prepared by dissolving, with frequent 
shaking, 30 grms. of pure indigo carmine paste in 1 litre of 
water. The solution is filtered into bottles having a capacit}^ 
of about 8| ozs., which, after careful closing, are heated in a 
water-bath to 158° F. for one hour. By heating to this tem- 
perature the formation of mycelium in the indigo solution is 
prevented, making the latter available for a long time. Only 
pure indigo carmine, especially free from indigo red, should be 
used for this solution, as otherwise the final point of reaction is 
difficult to determine on account of the reddish or brown shade 
appearing towards the close. If, on the other hand, the solu- 

' Zeitschr. f. aualyt. Cliemie, 1871, 1. 

2 Comptes rendus, xlvi. 44. 

3 Jouru. f. prakt. Chemie, Ixxxi. 150. 



EXAMINATION OF VEGETABLE TANNING MATERIALS. 155 

tion of indigo carmine is pure, the greenish color appearing 
finally passes suddenly over into a pure golden yellow. 

2. A tannin solution. Chemically pure tannin is dried at 
212° F. for a few hours, and 2 grms. of it dissolved in 1 litre of 
water. As the tannic acid should be as pure as possible in 
order to obtain accurate results, it is first tested by Hammer's 
method. 3 grras. of the tannic acid dried at 212° F. are for 
this purpose dissolved in 250 ce. of water, and the specific 
gravity determined with a picnometer. The tannic acid con- 
tained in 150 c.c. of this solution is precipitated with some 
green depilated skin, the specific gravity is again determined, 
and the tannic acid calculated as previously mentioned. To 
make the tannin solution, which is very much inclined to 
mould, durable, it is filled into small bottles having a capacity ' 
of about J oz. which are heated in a water bath to 158° F., 
and preserved lying on their sides. 

3. A solution of potassium manganate. This should be of 
such concentration that 12-14 c.c. of it will decolorize 20 c.c. of 
the indigo solution, and 9-10 c.c. effect the destruction of the 
tannic acid in 10 c.c. of the solution containing 0.2 per cent, of 
tannic acid. 1 c.c. of potassium manganate solution oxidizes 
consequently 0.0020-0.0022 grm. of tannic acid. Such solu- 
tion is obtained by dissolving 10 grms. of pure dry crystallized 
potassium permanganate in 61 grms. of water. 

4. A Y^j- normal solution of oxalic acid. In case sufficiently 
pure tannic acid cannot be obtained a jIq normal solution of 
oxalic acid prepared by dissolving 6.3 grms. of pure crystallized 
oxalic acid in 1000 c.c. of water, can be used for making the 
titre for the solution of potassium manganate. By comparative 
experiments, Neubauer found that 6.3 grms. of oxalic acid are 
equivalent to 4.157 grms. of tannic acid.^ To preserve the 

1 About 100 c.c. of tannin solution = 0.02 grm. of tannic acid, were, after 
adding 20 c.c. of indigo solution, titrated with potassium manganate solution, 
four determinations requiring, on an average, 7.1 c.c. of potassium manganate 
solution, 1 c.c. of the latter being therefore equal to 0.002817 grm. of tannic 
acid. 10 c.c. of the normal solution of oxalic acid required 14.6 c.c. of the 
same solution of potassium manganate, 0.063 grm. of oxalic acid being, there- 
fore, equal to 0.04118 grm. of tannic acid. Three experiments gave, on an 



156 THE MANUFACTURE OF LEATHER. 

oxalic acid from decomposition by fungus vegetation, it is 
heated in well-closed bottles to 158° F. for a few hours. 

5. Pure animal charcoal. Finely pulverized animal char- 
coal is completely extracted with hydrochloric acid and then 
washed with water by decantation until the reaction of chlorine 
disappears from the wash water. The animal charcoal thus 
prepared is preserved in a closed bottle under water. 

6. Pure dilute sulphuric acid. Making the litre. — The re- 
lations between indigo solution and potassium manganate solu-. 
tion are first determined by compounding 20 c.c. of indigo 
solution with 700 c.c. of water and 10 c.c. of dilute sulphuric 
acid, placing the beaker glass containing the fluid upon a white 
support — a white porcelain plate — and adding, with constant 
stirring, solution of potassium manganate until the solution, in 
the commencement deep blue, becomes first dark green, then 
pale green, next greenish-yellow, and finally golden-yellow. 
The addition of solution of potassium manganate must be 
made very carefully towards the end of the reaction, and the 
fluid thoroughly stirred after adding a few drops, as otherwise 
the final reaction may be easily exceeded. "With good indigo 
the transition from the greenish into the pure golden-yellow 
shade is quite sudden. After determining the consumption of 
solution of potassium manganate for 20 c.c. of indigo solution, 
the experiment is repeated with an addition of 10 c.c. of solu- 
tion of tannic acid, 20 c.c. of indigo solution, 700 c.c. of water, 
10 c.c. of sulphuric acid, and 10 c.c. of solution of tannic acid. 

From the number of cubic centimeters of solution of potas- 
sium manganate consumed, is deducted the quantity required 
for 20 c.c. of indigo solution, and then is found the number 
which was required by the 10 c.c. of solution of tannic acid. 
The effective value of 1 c.c. of solution of potassium manganate 
can be readily calculated by simple division. To control and 

average, 0.063 grm. of oxalic acid = 0.04157 grm. of tannic acid. By taking, 
according to Streeker, the molecular weight according to the formula Cj-HooOj, 
as 618, 15 molecules of C2H2O4, are according to the above determinations = 2 
molecules of tannic acid. 63 grms. of oxalic acid are equal to 41.20 grms. of 
tannic acid, while the practical expei'iment mentioned above gave 41.57 grms. 
of tannic acid. 



EXAMINATION OF VEGETABLE TANNING MATEEIALS. 157 

affirm the result, the experiment is twice repeated. Care must 
be had that the indigo solution is so concentrated that 20 c.c. 
of it require at least as much solution of potassium manganate 
as 10 c.c. of solution of tannic acid, or, what is surer, one-half 
more than the latter. The titre of the solution of potassium 
manganate must be frequently controlled. 

Where gallic acid appears in connection with tannic acid, 
Loewenthal's method as modified by Neubauer cannot be used. 
LoewenthaP has, therefore, altered his method in the following 
manner : — 

He makes two titrations, the first with the "original" solu- 
tion of the tanning material and the second with " the fluid 
freed from tannic acid by precipitation with glue or skin pow- 
der." The difference gives the quantity of potassium manga- 
nate consumed for the tannic acid. 

The glue solution is, according to Loewenthal, prepared by 
soaking 25 grms. of the finest Cologne glue in water over night, 
liquefying it the next day in a water-bath, saturating it com- 
pletely with pure common salt and diluting with saturated solu- 
tion of common salt to 1 litre. 

Kathreiner,^ who subjected this method to a thorough test, 
gives the following description of a suitable manner of execut- 
ing it: — ' 

The solution of potassium manganate used for titration is 
prepared by dissolving 1.333 grm. of crystallized potassium per- 
manganate in 1 litre of water. The strength of the indigo solu- 
tion used by Kathreiner and Loewenthal, is considered by them 
as exerting no influence upon the result. The concentration of 
the solution used by Kathreiner was such that 20 c.c. of it re- 
quired for oxidization an amount equal to 9-10 c.c. of potas- 
sium manganate. The only thing of importance is that the 
quantity of indigo used in titration requires at least 1.5 times 
the quantity of potassium manganate of that which is necessary 
for the oxidation of the oxidizable substances to be determined. 
The quantity of indigo solution to be added to the extract of 

1 Zeitschr. f. analyt. Chemie, 1877, 33, u. 201. 

2 Dingl. Polyt. Journ., ccxxviii. 54. 



158 THE MANUFACTURE OP LEATHER. 

tanning material to be tested, is determined by a preliminary 
experiment. It is advisable not to use too mncli solution of 
tanning material, as this would require the addition of such a 
large quantity of indigo as to make the coloring too dark to 
allow the final reaction to be judged with sufficient accuracy. 
For acidulating the titrating fluid, Kathreiner uses dilute sul- 
phuric acid (1 : 5) of 1,18 specific gravity. 

The original solution is to be filtered and the filtrate must in 
all cases be diluted to 2.113 pints. The duration of titration is, 
for the above conditions, about four minutes for the original solu- 
tion, and about six minutes for the filtrate precipitated with glue.^ 

The determination of the titre is effected, as in ISTeubauer's 
method, by a -^-^ normal solution of oxalic acid. Kathreiner 
executed the titration,^ on account of the final reaction being 

' Too high results are obtained by a too quick titration of the filtrate still 
containing glue. 

2 The process of determining the tannic acid in tanning materials, for in- 
stance in sumach, was as follows : — 

Experiment a. 

1. 10 c.c. of sumach } require for decolorization 13.9 c.c. of solution of potassium 
20 c.c. of indigo 5 manganate. 

2. 10 c.c. of sumach } require for decolorization 14.0 c.c. of solution of potassium 
20 c.c. of indigo ' manganate. 

20 c.c. of sumach and 40 c. c. of indigo re- } 27.9 c.c. of solution of potassium 

quire therefore, J manganate. 

From this is to be deducted for 40 c.c. of > 20.5 c.c. of solution of potassium 

indigo, J manganate 

Remainder, = 7.4 c.c. " " " 

20 c. c. of sumach solution require therefore, 7.4 c.c. " " " 

Experiment b. 

100 c.c. of sumach solution are compounded in a beaker glass with 
100 c.c. of glue solution and stirred, and to tliis are added 
50 c.c. of water, containing 2.5 grms. of sulphuric acid of 1.80 

specific gravity. 

250 c.c. cubic centimeters. 
This mixture remains standing covered over night, and is then filtered 
through a dry filter. 
50 c.c. of this filtrate titrated ^ 

with 1 litre of water and V 12.8 c.c. of solution of potassium manganate. 
20 c. c. of indigo, required, ' 
50 c.c. of the filtrate, and 20 ^ 

c.c. of indigo solution, and > 12.9 c.c. 
1 litre of water consumed, ) 



EXAMINATION OF VEGETABLE TANNING MATERIALS. 159 

easier recognized, in a white porcelain saucer instead of in a 
beaker glass. 

Kathreiner says :^ " It would be desirable in titrating the 
'filtrate' with the potassium manganate consumed for indigo, to 
be able also to deduct that consumed for the oxidizable sub- 
stances of the glue. This may be approximately attained by 
comparative experiments with skin powder. But in case the 
oxidizable substance of the glue is not precipitated in an equal 
proportion to the precipitated quantity of glue, only average 
values are, of course, again obtained, since a like quantity of 
glue is not always precipitated. The case is different, if the 
oxidizable substance of the glue is either not precipitated at all, 
or entirely. Until this question is definitely settled, I propose 
to bring half the ' glue error' into calculation. Besides the glue 
error becomes less by replacing the glue solution partly by 
saturated solution of common salt." 

In conclusion Kathreiner recommends the general introduc- 
tion of Loewenthal's improved method of determining tannic 
acid. 

Examination of Oak Barh. — 1. Preparation of bark extract. 
A microscopical examination of oak bark shows that the tannic 
acid is by no means equally distributed in all parts. By placing 

According to this 100 c.c. of the ^ 

filtrate, and 40 c.c. of indi- r 25.7 c. c. of solution of potassium manganate. 

go solution require 
Deduction for 40 c.c. of indigo 

solution, 
Remain for the 40 c.c. of the 

original sumach decoction, 
For the oxidizable substance 

(not tannic acid) a 40 c.c. 

of sumach decoction require 

therefore, 
Deduct for oxidizable substance 

Remainder, = 9.6 c.c. " " " 

Of the total quantity of tannic acid found by titration with solution of potas- 
sium manganate 64.86 c.c. are precipitable with glue, and 35.14 c.c. (oxidizable 
substance) 7iot precipitable with glue. 

' Dingl. Polyt. Jour., ccxxviii. 62. 



20.5 c.c. 
5.2 c.c. 




160 THE MANUFACTUEE OF LEATHER. 

a few cross cuts of young and old oak bark in glycerine, and 
adding a very small quantity of ferric chloride, the portions con- 
taining tannic acid can be distinctly distinguished with the 
miscroscope by the appearance of a beautiful blue or black 
coloring. 

The cells forming in young bark a ring between the middle 
and inner bark contain, according to Neubauer, no tannic acid 
whatever. It occurs scattered in the middle bark, in the last 
layer and rind. To obtain a correct average sample the ground 
bark should be thoroughly mixed, special attention being paid 
to the thorough mixing of powder and fibres, since the first, 
according to Neubauer, is richer in tannin than the latter. 

To obtain a correct sample, T. Kathreiner^ proposes the 
following method : Spread the samples taken from the different 
portions upon a smooth, clean support, so that the first sample 
occupies a surface of 15 square inches and lying 0.4-0.6 inch 
deep, and then add the second, third, and succeeding samples 
until the pile is from 4 to 6 inches high. Now take out in 8 to 
10 places samples of 15 square inches, and lay them in the order 
as taken upon each other ; but spreading them over one square 
foot of surface. The three or four samples of about 15 square 
inches each, which are to be tested, may be again laid one above 
the other before delivering them to the analyst. This method, 
of which the above is an example, must of course be changed 
according to circumstances as regards the extent of surface to 
be covered. Samples of nnground valonia are sometimes taken 
by breaking pieces from the separate rinds with a pair of 
pincers. Kathreiner advises the taking also of the part of 
the cup upon which the acorn sits, as this consists largely of 
cells containing only traces of tannin. 

Neubauer pulverizes a sample of 1000 grms. in a steel mill. 
A portion sufficiently large for analysis is completely dried in 
a water-bath at 212° F., and, while hot, placed in a carefully 
dried matrass, and this hermetically closed. When cold, the 
quantity required for preparing the aqueous extract is weighed 
off" in portions of 20 grms. each. It is best to extract an equal 

^ Gerberzeitung, xxiii. No. 12. 



EXAMINATION OF VEGETABLE TANNING MATERIALS. 161 

quantity of bark by boiling for an equally longtime. 20 grms. 
are boiled witli 750 c.c. of water for three-quarters of an hour. 
When cold the decoction is put in a litre flask and the latter 
filled with water to the mark and thoroughly shaken. The 
fluid is then allowed to settle, or is filtered. For each experi- 
ment 10-20 CO., according to the greater or smaller percentage 
of tannin in the bark, are taken out with a pipette.^ 

10-20 c.c. of this aqueous extract, 20 c.c. of indigo solution, 
10 c.c. of dilute sulphuric acid, and 750 c.c. of water are placed 
in a large beaker glass standing upon a white support, and solu- 
tion of potassium manganate is added from a Gay-Lussac or 
Geisler burette until the blue color passes over into a beautiful 
golden yellow. 

The objection was raised to this method of determination 
that the bark extract is not a pure tannin solution, but contains, 
as previously mentioned, a series of other bodies, and that the 
tannic acid occurring in oak barks, which Wagner designated 
as physiological is not identical with the pathological, i. e., the 
tannin of gall-nuts, to which the results are referred. Regarding 
the last objection, it must be admitted that the results obtained 
do not give the absolute percentage of tannic acid in the oak 
bark. The figures obtained are only relative, but perfectly 
comparable with each other. The tanner and technologist do not, 
as a general rule, care to know the absolute percentage of tannic 
acid, but only wish to find out how much more tannic acid one 
bark contains as compared with another, and for this purpose 
the method in question furnishes very useful results. 

But, on the other hand, the first objection, that oak bark con- 

1 Neubauer (Zeitsclir. f. analyt. Chemie, 1871, 32), shows that boiling even 
for three hours has no influence whatever upon the result, and that therefore 
Neubrand's assertion that tannic acid is decomposed by boiling in water, is 
incorrect. Neubauer confirms Lippowitz and Mittenzwei's opinion that a part 
of the tannic acid is more fixed and can only be extracted with difficulty or not 
at all by water alone. He found that a different result was obtained as regards 
the percentage of tannic acid in one and the same bark, according to whether it 
was extracted cold or warm. 

The percentage of tannic acid soluble with difficulty varies in the difterent 
barks. Barks extracted cold still contain some tannic acid which can be 
extracted by repeated boiling. 
11 



162 THE MANUFACTURE OF LEATHER. 

tains various organic substances which, by suffering destruction 
by the solution of potassium manganate, influence the results, 
cannot be denied. 

To these substances occurring in aqueous bark extracts belong 
among others, pecticacid, malic acid, fats, etc. Cech^ has already 
made experiments in regard to the behavior of dilute solutions 
of acetic, malic, tartaric, and citric acids, sugar, dextrin, gum, 
fat, caffeine, urea, etc., towards solution of potassium manganate. 
He found that these substances in dilute solutions are not 
oxidized, and only after some time when in a concentrated state. 

To avoid therefore any effect of the solution of potassium 
manganate upon the substances, it is only necessary, according 
to Cecil's proposal, to thoroughly dilute the bark extract. 

JSTeubauer, by repeated experiments, established the fact, that 
pectic acid exerts no influence whatever upon solution of po- 
tassium manganate. He found, in making these experiments, 
that pare animal charcoal possesses the property of withdrawing 
all the tannic acid from a fluid containing it in solution. Tak- 
ing this as a basis, Neubauer proposes the following modifica- 
tion of Loewenthal's method. 

The tannic acid contained in 10 to 20 c.c. of bark decoction 
is determined with solution of potassium manganate in the 
manner described above. Another portion of 10-20 c.c, is 
treated with pure animal charcoal until the filtrate, after an ad- 
dition of sodium acetate and ferric chloride, shows no reaction 
of tannic acid. The filtrate is compounded with 20 c.c. of 
indigo solution and 10 c.c. of dilute sulphuric acid, and the whole 
diluted with water to 700-800 c.c, and then titrated with po- 
tassium manganate. The number of cubic centimeters of po- 
tassium manganate is, after subtraction of the quantity required 
for the indigo, deducted from the cubic centimeters of potassium 
manganate found in the first titration, the quantity of pure tan- 
nic acid being calculated from the remainder. In the treatment 
with animal charcoal pectic acid and other substances suffering 
decomposition by potassium manganate remain in solution. 
The quantity of solution of potassium manganate required for 

' Zeitrichr. f. analyt. Cliemie, vii. 134. 



EXAMINATION OF VEGETABLE TANNING- MATERIALS. 163 

them is determined by itself and may be brought into the cal- 
culation. Substances not withdrawn by animal charcoal re- 
quired 0.20-0.25 c.c. of potassium manganate for 10 c.c. of 
bark extract. Too high results are obtained by Loewenthal's 
method from tanning materials containing, besides tannic acid, 
gallic acid which is also oxidized by solution of potassium man- 
ganate and withdrawn, like tannic acid, by animal charcoal. 
For such materials as, for instance sumach, valonia, dividivi, 
etc., it is best to use either Hammer's or Kisle Bennat's method. 

LoewenthaP himself has, as already mentioned, modified 
his method. In determining the tannic acid in barks he pro- 
ceeds as follows. He titrates first with solution of potassium 
permanganate in the presence of indigo solution, the quantity 
of solution of potassium permanganate consumed in this process, 
indicating the amount of tannic acid and other oxidizable sub- 
stances present. He precipitates then from a fresh measured 
portion of the bark extract all the tannic acid with glue, or 
as mentioned under flammer's method, with prepared skin 
powder, and filters after the precipitate has settled to the bottom. 
A measured quantity of the filtrate is then compounded with 
indigo solution and titrated with solution of potassium permanga- 
nate. The data for calculating the quantity of tannic acid are 
obtained by deducting the amount of solution of potassium 
permanganate consumed in the second titration from that in the 
first. This method gives, according to Proctor,^ good results 
and is easily executed. 

Comprehensive Comparison of the Results obtained hy the above 
described Methods. — We give here a tabular compilation by 
Hallwachs,^ who compared the different methods of determina- 
tion by analyzing the same bark according to various methods. 
The following figures show how great are the differences: — 

1 Zeitschr. f. analyt. Chemie, 1877, 33. 

2 Chem. News, 1877, No. 924, xxxvi. 

3 DingL Polyt. Journal, clxxx. 



164 



THE MANUFACTURE OF' LEATHER, 



Percentage of Tannic Acid determined according to the Method of 



Bark. 


Fehlinar, 
MuUer. 


Loeweuthal. 


Hammer. 


Fleck. 


Mittenzwei. 


A. . . . 


6.16 
6.11 
13.80 
9.74 
9.25 
8.90 




5.24 

5.25 

13.00 

9.00 

8.77 
8.00 






B . . . 








I . . . 
II . . . 

III . . . 

IV . . . 


13.24 
9.35 

9.28 
8.57 


12.10 

8.48 
8.15 
7.48 


14.07 

10.31 

10.22 

9.27 



According to this table, the results obtained by Mittenzwei's 
method are 0.5 to 0.8 per cent, too high as compared with those 
bj Fehling-Muller's and Loewenthal's methods. The results 
obtained by Fleck's method are the lowest, being 0.5 to 0.7 per 
cent. less than those by Fehling-Mueller's and Loewenthal's, 
which nearly agree. Between these two are the results obtained 
b}^ Hammer's method, which are somewhat lower than those 
by Fehling-Miiller's and Loewenthal's. By assuming with 
Neubauer that, in the presence of pectine, the results obtained 
by Loewenthal's method are too high, it appears that results, 
wbich nearly agree, are obtained by Hammer's and Loewen- 
thal's modified methods. 



Note. — For portions of the matter contained in this chapter the sources which 
have not been specifically indicated, the author desires to acknowledge his in- 
debtedness to Bolley's Technologie, 35 (Bd. vi. 4), Heinzerliug, also to Diction- 
naire de Chimie, Pure et Appliquee, Wurtz, iii. 193 et seq. 



WATER. . 165 



CHAPTEE IX. 

WATER. 

Section I. General Eemarks Concerning Water. 

Water occupies an important position in tanning, it being 
employed, on the one hand, for washing, cleansing, and pre- 
paring the raw hides, and on the other, as a solvent for all the 
tanning materials and as a diluent for all the coloring and dye- 
ing materials used. 

Empirics have frequently unfairly overestimated the impor- 
tance of water in tanning by declaring water containing more 
or less mineral constituents entirely unfit for the preparation of 
many varieties of leather. 

Although it cannot be denied that a higher or lower degree 
of hardness of the water is a factor deserving close considera- 
tion in the manufacture of leather, it must not be overestimated 
to such an extent as to lay the blame for obtaining a poor qual- 
ity of leather entirely upon the properties of the water. 

We will here briefly discuss the most important admixtures 
of water, and their influence in tanning. 

All naturally occurring water contains smaller or greater 
quantities of alkaline and earthy alkaline salts, and carbonic 
acid in solution. There is no entirely pure well or river water, 
i. e., free from all admixtures. By leaving out of consideration 
the small quantity of ammonium nitrite, organic substances, etc., 
held in solution by rain water, the latter might be considered 
chemically pure water. 

Water is distinguished as Itard and soft^ according to the 
quantity of earthy alkaline salts it contains, the amount of 
mineral substances varying from 1 milligrm. to 1 grra. per 
litre. The principal admixtures occurring in water are, as 
mentioned above, the alkalies, such as potassium, sodium, alka- 



166 THE MANUFACTURE OF LEATHER. 

line earths, lime, and magnesia ; the oxides of a few heavy 
metals in combination with ordinary mineral acids, sulphuric, 
nitric, phosphoric, carbonic, and hydrochloric acids. The gases 
held in solution are chiefly carbonic acid and atmospheric air, 
sulphide of hydrogen occurring but seldom. 

The admixtures of spring and well water consist principally 
of the constituents of the layers of earth through which it per- 
colates. Those, for instance, contained in the waters flowing 
through the doloraitic stratification may be considered as pure 
solutions of the dolomitic rock, consisting as they do of calcium 
carbonate, magnesium carbonate, and silicic acid, the quantity 
of all other, constituents being so small as to make it almost 
impossible to determine them by quantitative analysis. The 
waters percolating through the basalt and the new red sand- 
stone contain principally calcium carbonate, magnesium car- 
bonate, silicic acid, considerable quantities of free carbonic acid 
and small quantities of common salt, calcium sulphate, and 
sodium carbonate. The total dry residue of waters coming 
from the lias formation varies between 268 and 516 milligrms., 
the principal constituents being in this case also calcium car- 
bonate, 200 to 400 milligrms. per litre, magnesium carbonate 
(varying from 30 to 90 milligrms. per litre), sodium carbonate, 
free carbonic acid, etc. 

Besides these natural constituents, spring and well water, but 
especially the latter when in large cities or in the neighborhood 
of dumping places for all kinds of offal, the soluble substances 
of which percolate through the soil, contain frequently in solu- 
tion organic products of decomposition of organized bodies such 
as bacteria, fungi, alkaline nitrates, especially ammonia, and 
alkaline salts. Though such water, for hygienic reasons, is 
generally unfit for drinking purposes, it may be put to techni- 
cal use. 

In determining the qualities of water for tanning purposes, 
two points, as mentioned, must be taken into consideration, viz., 
first, the behavior of the water when used as a solvent for the 
tanning materials, and second, whether it is adapted for pre- 
paring the hides for tanning. If the water is to be used for 
dissolving or extracting tanning materials containing tannic 



WATER. 167 

acid, tlie earthy alkalies, lime and magnesia combinations, exert 
a decidedly injurious effect, as, by forming insoluble combina- 
tions with the taimic acid, they render a part of the tanning 
material useless. If the water is to be used for soaking, cleans- 
ing, and washing the hides, mineral admixtures may exert a 
favorable influence. In speaking of the chemical properties 
of the skin tissue and the coriin, we mentioned that some 
of the alkaline salts exert a dissolving influence upon the 
intercellular substance or coriin, the effect of small quantities 
of alkalies being an increased solution of coriin in acids. From 
this we may draw the conclusion that hard water promotes the 
soaking of dried hides, but that a part of the coriin is withdrawn 
from the skin tissue if the hide is too long subjected to the action 
of the water.'^ 

Hides intended for sole leather are siuelled or "plumped" in 
order to cause them to be better adapted to the absorption of 
the tanning material. In case the natural swelling is not suffi- 
cient, it is assisted by the use of inorganic as well as organic 
acids. This swelling process is, for the reasons previously 
stated, accelerated, and the falling back of the hides into their 
previous state prevented by the use of hard water. 

Soft water is preferred for the manufacture of upper leather, 
as the hides must not be swelled as much as those for sole 
leather, as otherwise the smooth cut would be injured. 

The temperature of the water used for preparing the hides 
must also be taken into consideration. Generally speaking, the 
water should be as cold as possible for the manufacture of sole 
leather to prevent the skin fibre from being softened too much. 

• Eitner (see Der Gerber, 1877, No. 178, and Diiigl. Polyt. Journ., ccxxiv. 
524) has made experiments as regards the effect of different inorganic constitu- 
ents of water upon the depilated skin, using various solutions of alkaline, cal- 
cium, and magnesium salts in distilled water. He found that water containing 
only calcium chloride and magnesium chloride had almost no swelling effect, 
and distilled water scarcely any, it being further remarked that carbonic acid, 
and consequently water containing bicarbonates, exerted a swelling effect upon 
the hide. Alkaline chlorides and alkaline earths, such as magnesium chloride, 
potassium and sodium chlorides, have no swelling effect whatever, even nullify- 
ing it partly. Calcium and magnesium sulphates proved the best swelling 
materials for hides, this explaining the advantageous effect produced in swelling 
by a careful addition of sulphuric acid to water containing much bicarbonate. 



168 THE MANUFACTUEE OF LEATHEE. 

It is also of importance that the water should not be exposed 
to too great variations in temperature in summer and winter ; 
46 to 50° F. may be designated as the most favorable tempera- 
ture. Spring water coming from deeper strata of the soil, and 
possessing consequently a more even temperature, is to be pre- 
ferred to river water. 

In the manufacture of waxed-calf, it is important that there 
should be a uniform temperature of the water in which the 
skins are soaked, and but few of the best manufacturers of this 
class of leather in France or Germany soak the skin in the run- 
ning water of the river, because it is extremely cold in winter 
and warm in summer. In default of water from a live source, 
it may be drawn from the cistern ; but you will say, it requires 
a large quantity of water, and that it will be costly to draw it 
to the surface. But it is very seldom that a tannery does not 
possess a horse or a steam engine ; the horse is often idle in the 
stable ; the engine has always a little power to spare above 
its requirements ; or by means of the simplest machinery a 
double action pump may be constructed and made to work by 
horse or steam power, and in this way there can be obtained 
from 2000 to 2500 gallons per hour more if desired. There 
should be in the centre of the tannery or in one of the corners, 
a large tank raised at least six feet above the ground; the 
water, pumped into the tank, can be distributed at will over the 
whole establishment. The total expense may amount to $500 
or $600 ; and such a figure is not large in consideration of the 
importance of the result : to have always at disposal a quantity 
of pure water and of an equal temperature. It makes a much 
greater difference in the manufacture of waxed-calf than with 
any other class of leather, whether the water is hard or soft ; 
still some prefer it soft, as it contains less calcareous substances 
than hard water, which is, as we have explained, often saturated 
with earthy salts. "We do not pretend to give in this work the 
analyses of all the waters that trickle through our soil ; it is 
the tanner's business to become acquainted with the quality of 
the water he has at his disposal, and to utilize it according to 
the elements it contains. Study the water ; if it is soft the 
■soaking will be done promptly, if it is hard it will take longer; 



WATER. 169 

but, any way, there is a certainty of arriving at the same result ; 
that is the aim. 

As regards the chemical examination of water, we refer the 
reader to the following section of this chapter. 

SectiojSt II. Methods for Determining the Constituents 

OF Water. 

We cannot enter upon a description of the different qualita- 
tive and quantitative methods of determining the constituents 
of water ; but will only briefly describe a few examinations of 
importance in tanning, and those who may desire a full descrip- 
tion of the methods and apparatus employed, are referred to the 
treatises of Wanklyn and Frankland on Water Analysis. 

The qualitative examinations of water as to its admixtures 
of lime, magnesia, 'alkalies, chlorine combinations, sulphuric 
and carbonic acid, the larger or smaller quantity of which gen- 
erally determines its character, can be executed in the follow- 
ing manner : — 

1. The chlorine combinations are shown by the formation of 
a white precipitate when treated with nitrate of silver in nitrate 
solution. 

2. Sulphuric acid and sulphates are recognized by the forma- 
tion of a white precipitate with barium chloride. 

3. Carbonic acid is present when the addition of clear lime- 
w^ater gives a white precipitate. 

4. The presence of silicic acid, lime, and magnesia, by evapo- 
rating to dryness with an addition of hydrochloric acid in a 
platinum dish of a capacity of about 1 litre. The residue is 
taken up with hydrochloric acid and water, the portion remain- 
ing undissolved being silicic acid. The lime can be separated 
as calcium oxalate from the filtrate with ammonium oxalate. 
After removing the calcium oxalate by filtration and evapora- 
tion of the filtrate, the magnesia is precipitated with ammonium 
phosphate as ammonium magnesium phosphate. 

5. Organic substances are shown by adding a few drops of 
potassium permanganate and some pure sulphuric acid. If or- 
ganic substances are present, the potassium permanganate. 



170 THE MANUFACTURE OF LEATHER. 

added drop by drop, is decolorized until all the organic sub- 
stances are completely oxidized. 

6. Determination of the entire residue. 1 litre is carefully 
evaporated to dryness, requiring from twenty-four to twenty- 
six hours, in a platinum dish, the weight of which has been 
previously determined. The residue is dried at 356° F. until 
a decrease in weight no longer takes place. 

7. A determination of hardness with alcoholic soap solution 
serves in most cases for tanning purposes as a substitute for a 
quantitative analysis. We give, therefore, a short description 
of it. 

The process of determining the hardness of water by a soap 
solution of a determined percentage, which was introduced by 
Clark, is a very simple one. By an addition of soap solution 
to water containing too much lime or magnesia, a white pre- 
cipitate of lime or magnesia soap insoluble in water is formed 
as long as calcium or magnesium salts are present. When an 
excess of soap solution has been added, the end of the reaction 
is indicated by the formation of lather on shaking the fluid. 

The effective value of the soap solution is determined by 
testing it with a lime solution of a determined percentage. 
Clark's method is, according to Faisst and Knauss, executed in 
the following manner : — 

The soap solution required for titration is obtained by dis- 
solving 30 grras. of dried soda soap in 3 litres of alcohol of 90 
per cent. The turbid solution is filtered and preserved for use. 
200 grms. of this concentrated solution are first compounded 
with 150 grms. of water (in order to reduce the alcohol to the 
strength of 56° Tralles, which has been proven to be the most 
suitable), and then with 130 grms. of spirit of wine of 56° 
Tralles. 45 c.c. of the solution thus obtained are required for 
the precipitation of 12 milligrms. of lime in 100 c.c. of water. 
The exact titre of this solution must be further determined and 
corrected by adding concentrated soap solution, or alcohol of 
56° Tralles, so that 12 milligrms. of lime require exactly 12 
milligrms. of soap solution. For the determination of the con- 
centration of the soap solution a neutral solution of calcium 
chloride is used, which is obtained by dissolving 0.214 grm. of 



WATER. 171 

calcium carbonate in hydrochloric acid, evaporating the solu- 
tion, and dissolving the residue to 1 litre. 100 c.c. of this 
solution contain 12 milligrms. of calcium oxide, or an equiva- 
lent quantity of calcium chloride. With this solution the soap 
solution is tested, and the latter sufficiently diluted, so that 
exactly 45 c.c are required to produce, when brought together 
with 100 c.c. of lime solution, and shaken, a white lather re- 
maining for about five minutes. 

The process of determining the hardness is as follows : A 
distinction is made between "total hardness" and "permanent 
hardness." The hardness of water not heated is called "total 
hardness," and the hardness produced by the earthy sulphates 
is termed "permanent hardness," because unaffected by ebulli- 
tion. The term " temporary" or " changeable hardness," being 
also frequently used to denote the hardness produced by the 
earthy carbonates, because removable by ebullition. 

1. Determination of Total Hardness. — 100 c.c. of water are 
measured with a pipette into a glass, having a capacity of 200 
c.c, and provided with a ground stopper. Water containing 
much lime is previously diluted with distilled water, so that to 
a determined number of cubic centimeters (10, 20, or 30) of the 
water to be tested, 90, 80, or 70 c.c. of distilled water are added. 
A mark on the glass indicates the point to which it is filled by 
100 c.c. of the fluid. 

Before adding the soap solution, the free carbonic acid is 
partly removed by shaking the water. 

As most well-waters have more than 12° of hardness, only 
10 c.c. of the water to be tested are measured off, and diluted 
to the mark with distilled water. Titrated soap solution is 
then slowly added from a burette until, after vigorous shaking, 
a dense delicate lather is formed which will hold for about five 
minutes. The soap solution is first added in half cubic centi- 
meters and later on in drops. The shaking must always be 
done in the same manner, and the volume of the fluid amount 
to 100 c.c. before the soap solution is added. Should a second 
experiment be necessary, the same quantity of water is used, 
or, in case but little soap solution has been consumed for the 
diluted water (10 : 100), correspondingly more (25-50 c.c), so 
that the quantity of soap solution, which should previously be 



172 



THE MANUFACTUEE OF LEATHER. 



approximately calculated, does not exceed 45 c.c. With the 
assistance of the following table, the respective degree of hard- 
ness which, in case the water has been diluted, must be multi- 
plied with the corresponding figure, is found from the cubic 
centimeters of soap solution consumed. (The corresponding 
figure is found bj dividing 100 by the cubic centimeters used 
for the experiment.) 



3.4 c.c. soap solution consumed . 


0.5 degree of hardness. 


5.4 " " 


. 1.0 


7.4 " " 


. 1.5 


9.4 " " 


. 2.0 



The difference of 1 c.c. of soap solution = 0.25 degree of 
hardness. 



11.3 c.c. 


soap solution consumed 


. 2.5 d 


3gree 


of hardness 


13.2 " 


" " " 


. 3.0 






15.1 " 


" 


. 3.5 






17.0 " 


" 


. 4.0 






18.9 " 


" " " 


. 4.5 






20.8 " 


i< <i <i 


. 5.0 







The difference of 1 c.c. of soap solution = 0.26 degree of 
hardness. 



22.6 c.c. 


soap solution consumed . 


5.5 degree 


of hardness 


24.4 " 


" " " 


. 6.0 


" 


26.2 •' 


1( U (( 


. 6.5 


(f 


28.0 " 


tl (t (1 


. 7.0 




29.8 " 


(1 11 1( 


. 7.5 


u 


31.6 " 


" " " 


. 8.0 " 


u 



The difference of 1 c.c. of soap solution = 0.277 degree of 
hardness. 



33.3 c.c. 


soap solution consumed . 


8.5 degree of hardness 


35.0 " 




. 9.0 


36.7 " 




. 9.5 


38.4 " 




. 10.0 


40.1 " 




. 10.5 


41.8 " 




. 11.0 



The difference of 1 c.c. of soap solution = 0.294 degree of 
hardness. 



43.4 c.c. soap solution consumed . 
45.0 " " " " 



11.5 degree of hardness. 
12.0 " " 



The difference of 1 c.c. of soap solution = 0.31 degree of 
hardness. 



WATER. 178 

Suppose 50 CO. of the water to be tested had been placed in 
the glass and diluted with 50 c.c. of distilled water, and had 
consumed 22.6 c.c. of soap solution for the formation of lather. 
According to our table these 22.6 c.c. of soap solution corre- 
spond to 5.5 degrees of hardness. This figure 5.5 is multiplied 
bj 2, which gives 11 as the actual degree of hardness of 
the water, (The figure 2 is obtained by dividing 100 c.c, bj 
50 c.c.) 

2. Determination of Permanent Hardness. — For the determi- 
nation of the permanent hardness 500 c.c, of water are boiled 
in a sufficiently large matrass for at least one and a half hours, 
a part of the evaporated water being replaced by distilled water. 
The boiled water, when cold, is poured into a flask having a 
capacity of 500 c.c, and the matrass rinsed out with distilled 
water, the rinsing being added to the water in the flask. The 
latter is then filled with distilled water up to the mark, and the 
entire contents filtered through a dry filter into a dry glass. 
The degree of hardness of a definite number of cubic centime- 
ters is then determined in the above manner, 

Clark was the first to introduce the term '• degrees of hard- 
ness," 1 degree corresponding, according to him, to 1 part 
(grain) of calcium carbonate or its equivalent of another cal- 
cium salt, or equivalent quantities of magnesia or magnesium 
salts in 70,000 parts (=1 gallon) of water. At the present time 
1 degree of hardness is suitably estimated as equal to 1 part 
of calcium oxide in 100,000 parts of water. The German de- 
grees of hardness are reduced to English by multiplying the 
degrees found by 5 and dividing by 4, the reduction of English 
to German degrees being vice versa, accomplished by multiply- 
ing by 4 and dividing by 5. In France 1 degree of hardness is 
calculated as equal to 1 part of calcium carbonate in 100,000 
parts of water, 1 degree of hardness being therefore : — 
In Germany = 10 milligrms. of calcium oxide in 1 litre of 

water. 
In France = 5.6 milligrms. of calcium oxide in 1 litre of water, 
or an equivalent quantity of magnesia or magnesium 
salts. 



PART III. 



CHAPTEEX. 

BARK — THE NATURE OF BARK — TOOLS USED IN BARKING — ROSS- 
ING BARK — LIST OF AMERICAN PATENTS FOR BARK-ROSSING 
MACHINES — PREPARING BARK FOR TRANSPORTATION — LIST OF 
AMERICAN PATENTS FOR PREPARING BARK FOR TRANSPORTA- 
TION. 

Having in the preceding chapters treated of the various 
barks used in tanning, we shall now, previous to taking up the 
subjects of grinding and leaching bark, discuss the manner and 
time for peeling, etc. 

Bark is the outermost covering or rind of vegetables. It en- 
velops the whole plant from the extremities of the roots to the 
extremities of the branches. If a branch of a tree be cut across, 
and we inspect such a horizontal section with attention, we per- 
ceive that the bark is composed of three distinct bodies, which, 
with a little care, may be separated from each other. The 
outermost of these bodies is called the epidermis, the middle one 
is called the parenchyma, and the inner one, or that next the sap 
wood, is called the cortical layers. 

The epidermis is a thin, transparent membrane, which covers 
all the outside of the bark, and it is, however, generally seen 
only in annual stems, or in the younger parts of woody stems. 
When inspected with a microscope, it appears to be composed 
of a number of slender fibres crossing each other and forming a 
kind of network. It seems even to consist of different thin, 
retiform membranes, adhering closely together. This at least 
is the case with the epidermis of the birch, which Duhamel 
separated into six layers. The epidermis, when rubbed off", is 
reproduced. In old trees, it cracks and decays, and new epi- 



BARK. 175 

dermides are successively formed. This is the reason that the 
trunks of many old trees have a rough surface, 

Davy was induced by some observations of Mr. Coats, of 
Clifton, to examine the epidermis of the bamboo, the sugar-cane, 
and the Eq-nisetum hyemale. He found in them a great quantity 
of silica. When examined under the microscope, the epidermis 
of these gramineous plants constitutes a brilliant retiform tissue, 
which gives it the harsh feel by which it is distinguished. The 
epidermis of the bamboo was found to contain 17.4 per cent, of 
silica, and it has the appearance, when pulverized, of pounded 
glass. He also found silica in the epidermis of the sugar-cane, 
the common bog reed [Arundo phragmites), wheat, barley, and 
oats. He found a still greater proportion of silica in some 
other of the gramineous plants. 

The parenchy7na lies immediately below the epidermis, it is of 
a deep green color, very tender and succulent, the outer layer 
of which is called epiphloeum^ and the inner layer rnesojMceum. 
Within the mesophloeum is a distinct layer called liber or endo- 
,p)hIoeum. When viewed with a microscope, the parenchyma 
seems to be composed of fibres which cross each other in every 
direction. Both in it and the epidermis there are numberless 
interstices, which have been compared to so many small blad- 
ders. 

The cortical layers form the innermost part of the bark, or 
that which is contiguous to the alhurnwm or sap-wood. They 
consist of several thin membranes, lying one above the other; 
and their number appears to increase with the age of the plant. 
Each of these layers is composed of longitudinal fibres which 
separate and approach each other alternately, so as to form a 
kind of network. The meshes of this network correspond in 
each of the layers, and they become smaller in every layer as it 
approaches the wood. These meshes are filled with a green- 
colored cellular substance, which has been compared by anato- 
mists to a number of bladders adhering together, and communi- 
cating with each other. The bark increases by the addition of 
an annual layer on its inner surface, next to the alhuriium or 
cambiu'in^ through which the sap circulates. 

Fourcroy supposes that the epidermis is the same, in its 



176 THE MANUFACTURE OF LEATHER. 

nature in all trees, and that it possesses constantly the proper- 
ties of cork ; but this opinion is not verified. The cortical 
layers seem, at least in many cases, to have a similar fibrous 
basis; a basis possessing essentially the properties of flax, which 
is itself merely the cortical layers of linum. usitatissimuin. Com- 
raon cork, which constitutes the epidermis of the Quercus suher^ 
is composed of a cellular tissue, whose cavities contain a variety 
of foreign substances, which may be separated by rasping down 
the cork and treating it by various reagents, as is done with 
wood, in order to free the liynin from foreign matters. Ten 
parts of common cork, when treated in this way, are reduced 
to seven, - This residue is considered by Chevreul as a peculiar 
substance, which he distinguishes by the name of suberin. 

We have already stated that bark is composed of four parts; 
all are not equally rich in tannin, or rather some contain none. 
Such is the case with the epidermis, the liber contains very 
little. It is in the inner layer of the cortex that it is principally 
found. 

Peeling the Bark and the Most Conveme7it Time for it. 

Experiment has demonstrated that it is in the spring, when 
the sap is in full activity, that the bark should be peeled. We 
have said that all the regenerating and vivifying power resided 
in the bark. The suckers, the slips, the buds present us a 
proof of this first fact. The willow, olive, mulberry, and a 
multitude of other trees, the trunks of which are entirely 
rotted and the bark alone forms the support, are often covered 
with leaves and flowers. This is due to the great quantity 
of nutritious juices conveyed by the bark. These abundant 
juices are sometimes difierent from those of the wood. Often, 
also, while of the same nature, they are in so great a propor- 
tion that they break the bark in order to exude, or it is suffi- 
cient to make incisions to have them run out. Almond trees, 
acacias, apricot trees, etc., are examples. It results from these 
facts, that while the sap is abundant in the bark in the spring, 
principally towards May, that that is the proper time for 
barking. Independently of numerous experiments of tanners, 
which demonstrate the superiority for tanning of the bark cut 



BAEK. ■ 177 

in the spring, chemical analysis throws light on this important 
fact. Indeed, Davy has demonstrated that 

Oak bark cut in the spring contains of tannin . • 6.04 

" " " fall " " " . , , 4.38 

Which gives nearly one-third more in the spring. Here 
theory agrees with practice, both recommending the spring as 
the time when the bark is richer in sap and tannin. The bark- 
ing is done by cutting circularly the bark from the trunk at 
both ends, and splitting it longitudinally. The bark is dried 
slowly in the shade, and care is taken to protect it from mould. 

Influence of Seasons and Place at the Time of Barhiny on the 
Richness in Tannin. 

We have said above that the spring is the best time to bark, 
but this time may be more or less advanced according to the 
temperature. Thus, if the winter has been severe and the 
spring cold, it will be only in the middle or the end of May that 
vegetation will begin, and the barks will not be so rich in tan- 
nin. On the contrary, if the winter has been mild and the 
spring warm, April is the most convenient time. In temperate 
climates it is by the end of April, or the beginning of May, 
that this operation commences. The barks are much richer in 
tannin as they come from trees of warm countries, ^. e., the 
tannin is developed in greater proportions the further south it 
is. In the same locality oaks well exposed to the south and in 
dry and elevated places give barks richer in tannin. On the 
contrary, if they are in the shade in a low and damp locality 
they contain less. It is the same for rainy seasons, which have 
great influence in the production of tannin. The barks are 
aqueous and sur-saturated with vegetable matter. These facts, 
while apparently trifling, are of decided interest to tanners. 

Tools used in Barhiny. 

In addition to the axe or hatchet for slitting the bark and 
making the cuttings around the trunk, thereby enabling it to 
be removed in lengths, the workmen employed in this opera- 
tion require other tools which they call "spuds" or "peeling 
12 



178 



THE MANUFACTURE OF LEATHER. 
Fi?. 10. 




irons," which are worked underneath the bark in order to 
loosen it. A. set of these tools is shown in Fig. 10. 

A Contrivance for cutting Barh lyreparatory to Peeling. 

The invention shown in Figs. 11 to 15, which is the idea of 
Mr. J. Daigneau of St. Hvacinthe, in the Province of Quebec, 
Canada, relates to a new and improved machine for cutting bark 
into suitable lengths around a log or trunk of a tree. In peeling 
bark for tanning or other purposes such cuttings have com- 
monly been done hitherto by the axe after felling the tree ; but 
by this machine the work of cutting around the tree can be 
done much more expeditiously and with better results. 

In obtaining bark the usual practice is, first, to fell the tree, 
and then measure off four feet, or the desired length, and then 
cut the bark around the trunk with an axe, and thus to measure 
and cut the bark the whole length of the tree trunk. This 
machine consists of a long lever or bar, made of wood or any 
suitable material, having near one end a mortise or slot cut 
through the lever, and through this mortise is inserted the 
shank of a knife-holder, and the shank is adjustable in the 
mortise and held there by a bolt or pin which passes through 
the bar and shank ; the machine is somewhat in appearance 
and mode of use like what is commonly known as a " cant-hook" 
for rolling logs. 

Figure 11 is a side elevation with a section of a tree-trunk to 
which the machine is applied. Fig. 12 is a view of the under 



BARK. 



179 



side of the bar, tlie knife being removed. Fig. 13 is a side and 
bottom view of the knife and knife-holder and spring detached 



Fig. 11. 




Fis:. 12. 



*»f ,«. 




Fis. 13. 



,-f .^' 




Fig. 14. 



Fig. 15. 





from the lever or bar. Fig. 14 is a cross-section of the knife- 
holder and knife, showing how the knife is held to the holder. 
Fig. 15 is a partial side view of the y -shaped knife detached 



180 THE MANUFACTUEE OF LEATHER. 

from the knife-holder, showing tlie form of the knife, and the 
slots (/, through which pass the bolts/, as seen in Fig. 14:. 

The letter A represents the bar or lever; B, the knife-holder; 
C, the U -shaped knife ; D, a section of a trunk of a tree ; a, the 
mortise in the lever, and a' a bolt passing through the lever 
and knife-holder; b, holes in the shank of tlie knife-holder; c, 
holes through the lever ; d, a spring attached by a screw, d', to 
said lever, having a slot, d", at its point of fastening ; e, a spring 
on said knife-holder, and e' an adjustable screw operating said 
spring e ; /, screws holding the knife to the knife-holder, and 
g g, slots in the ends of the knife. 

The lever A in practice is five or six feet long, and is made 
of wood. It has holes c (see Figs. 11 and 12), through which 
passes the pin or bolt a', and these holes pass through the 
mortise or slot a. These holes are for the purpose of adjusting 
the knife-holder to the size of the tree-trunk, as also are the 
holes b in the shank of the knife-holder. The knife-holder 
(see Figs. 11 and 13) is from one to three or more feet in 
length, and is made of metal, and pronged at one end for the 
purpose -of holding the y 'Shaped knife. This holder has a 
spring, e, on its under side, against which presses an adjustable 
screw, e', which passes through the holder. (See Figs, 11, 12, 
13, 14.) It will be observed that the spring, which is fastened 
to the lever by a screw, e', presses upon the spring and adjusts 
it to the tree-trunk, and is a guide for the thickness of the bark. 

Fig. 14 shows the method of adjusting the knife to the holder. 
The screws/ pass through the slots g from the inside, and are 
made fast by nuts on the outside. The slots g serve to adjust 
the knife to the thickness of the bark by raising or lowering 
the knife. Fig. 11 shows how the machine is applied to the 
tree-trunk, whether the tree is standing or cut and fallen. 

To save the bark before felling the tree it is usual first to cut 
around the trunk of the tree near the ground, and then above, 
the length or one cutting, and strip off the bark. The tree is 
then felled and trimmed. The workmen then pass along, one 
on each side of the trunk, for convenience and expedition of the 
work, and one workman takes the machine by the handle and 
applies it in the manner shown in Fig. 11, and c its from the 



BARK. 181 

under side to the upper side of the trunk and passes the machine 
to the workman on the other side of the trunk, who cats the 
remaining part in tlie same manner. 

The advantage of this form of knife is readily seen. The 
cutting is a grooved one, and leaves the edges of the bark 
smooth and of even length, with but little waste. 

In small trees having thin bark a single or straight knife- 
blade might accomplish the cutting; but in thick bark the 
knife would be liable to break. 

It will be observed that the spring d, attached to the lever A, 
and the spring e to the holder B, partly clap and press against 
the tree-trunk. 

They guide and aid the knife and steady the machine. 

Rossing Barh. 

The outer coating of bark after continuous exposure to the 
action of the elements loses all its tanning properties, and the 
process of stripping this outer from the inner layer of bark is 
technically termed " rossing," and it is essential that the work 
when it is attempted should be perfectly done, for if any material 
quantity of the outer layer of bark be left on the inner one the 
process of tanning leather is unnecessarily prolonged, as the 
dead coating of bark has to be tanned along with the leather, 
and then again the leather when thus tanned has an undesirable 
dark color. 

The bark from which tannin is obtained is, as we have seen, 
composed of the cortex or layer which contains the tannic 
acid, the cellular integument next thereto which contains the 
coloring matter, and the epidermis or outer bark. What thick- 
ness of the cellular integument should be removed from the 
whole bark has long been an open question and one upon which 
there has been and still is a wide difference of opinion. 

It seems to be questioned whether rossing will repay the 
tanner after the bark is delivered on his premises; the cost of 
doing this work being from 40 cents to 50 cents per ton, and 
the material removed from the bark weighing on the average 
about 450 lbs. 

There is no question but that it would often pay tanners to 



182 THE MANUFACTURE OF LEATHER. 

have this work done before the bark is shipped. To pay the 
freightage, and handle, grind, and leach 20 or 25 per cent, of 
worthless material, when it could be removed in the first in- 
stance at but a small cost by a suitably contrived bark-rossing 
machine, is not economy. 

The loss in the leach and tan- vats is twofold, for not only does 
this worthless material occupy valuable space, but it absorbs 
tannin that could more profitably be employed for tanning 
leather. 

List of all Patents for Bark Rossing Machines issued by the Govern- 
ment of the United States of America, from 1790 to 1883 inclusive. 



No. 




Date 




Inventor. 


Eesidence. 


37,530 


June 


9, 


1863, 


B. F. Taber, 


BuflFalo, N. Y. 


38,861 


July 


27, 


1863, 


R. Healy, 


Swanton Falls, Vt, 


39,888 


Sept. 


15, 


1863, 


J. Cowie, 


Portland, Me. 


110,403 


Dec. 


20, 


1870, 


G. S. Tallingast and 
J. W. Burdwin, 


Morrisville, N. Y. 


128,612 


July 


2, 


1872, 


C. Gilpin and J. T. 
Hill, 


Cumberland, Md. 


141,448 


Aug. 


5, 


1873, 


J. Martin and G. W. 
Wilson, 


Morenci, Mich. 


153,492 


July 


28. 


, 1874, 


J. Moulton, 


Ossipee, N. H. 


176,709 1 

Reissue \ 

7,264 J 


April 


25, 


1876, 


S. R. Thompson, 


Portsmouth, N. H. 



Preparing Tan-harlc for Transportation. 

Various methods have been devised for preparing tan-bark 
for transportation. Heretofore the exportation has been at- 
tended with great cost, owing to its bulky nature and the lia- 
bility of the acids in the bark causing it to ferment and spoil 
when piled in bulk, especially in a broken or pulverized condi- 
tion. 

Sometimes the bark has been ground and pressed and then 
coated with tan-liquor on the exterior of the blocks in order to 
preserve it. 

Mr. Wm. H. Smith, of Chicago, 111., takes the tan-bark after 
it has been ground in the usual way, and places it in a strong 
mould, and subjects it to compression by percussion, using for 
the purpose, preferably, a powerful steam.-hammer. Under the 



BARK. 



183 



influence of the hammer the tan-bark will readily compress to 
a density of from sixty to eighty pounds per cubic foot, forming 
a solid self-cohering block of great strength and tenacity, and 
when removed from the mould, suitable for exportation or ship- 
ment without being inclosed in any covering. These blocks 
may be made cylindrical, rectangular, or of any form desired, 
and of any suitable size. It is preferable to make them, how- 
ever, of about one hundred pounds weight. The tan-bark thus 
prepared in blocks it is claimed will not ferment or spoil, as the 
air has an opportunity to circulate around each separate block, 
and there is consequently no tendency to heat or ferment, as is the 
case where ordinary pulverized tan-bark is piled in bnlk. The 
tan-bark should be in a dry state when placed in the mould, and 
if it contains much moisture it should be expelled by desiccation 
before the material is compressed. The blocks, when placed in 
warm water, will soon disintegrate and the particles resume 
their original size and shape, so that the blocks of bark may in 
this way be very easily put in condition for use. 

The term " self-cohering," used in describing these blocks, in- 
dicates that the particles composing the blocks cohere together 
naturally without the agency of any adhesive admixture. 



List of all Patents for Methods and Machines for Packing Tan-bark 
for Transportation^ issued hy the United States of America, from 
1790 to 1883 inclusive. 



No. 



Date. 
June 6, 1812, 

June 5, 1815, 



182,965 1 
Reissue ^ 

10,211 

10,230 

184,638 Nov. 21, 1876, 
195,377 Sept. 18, 1877, 
247,125 Sept. 13, 1881, 



Inventor. 
J. Richardson and 

B. Stout, 
J. Logan, 



Oct. 3, 1876, J. Sherman, Jr. 



R. Loechner, 
C. Kimpler, 
W. H. Smith, 



Residence. 
Bucks County, Pa. 

Philadelphia, Pa. 

Chicago, III. 

New York, N. Y. 
Chicago, 111. 
Chicago, 111. 



184 THE MANUFACTURE OF LEATHEE. 



CHAPTER XL 

GRINDING, CUTTING, CRUSHING, AND CONVEYING TAN-BARK — 
LIST OF AMERICAN PATENTS FOR BARK-MILLS. 

Section I. Grinding, Cutting, and Crushing Tan-bark. 

There are but few requirements of the tanner's business that 
demand a greater amount of attention, or in which there is so 
much room for economy, as in the grinding and leaching of 
bark. 

One of the prime requirements of a good bark-mill is that it 
should yield the ground bark in a uniform condition, not par- 
tially in a coarse and partially in a poAvdered state; as the dust is 
an obstruction to the penetration of the tannin by thickening 
the tan-liquor, and injures the leather in appearance and quality. 

The more unevenly bark is ground, the more unevenly it is 
leached ; the most accessible particle has to stay in the leach 
until the most dif&cult has been disintegrated. If the ground 
bark could be very fine and perfectly uniform — which is quite 
impracticable — the concentration of strength of liquors would 
be much greater than we now get; it is well to approach as 
near to that result as a little care will enable one to do. 

If the larger pieces are small enough, and the whole is well 
mixed, the bark is in condition for thorough leaching, for the 
leaching fluid will readily enter the whole mass. Bark dust is by 
no means impenetrable, but does not admit of as rapid passage 
of the fluid as the larger particles, and will shed it to a very 
large. extent if the dust is allowed to accumulate in one place and 
be absent in another; the mixing of bark prevents this. When 
bark dust is penetrated, all its tannin is at once absc»rbed by the 
leaching fluid ; this is not much, however, as the dust comes 
chiefly from the dead, useless parts of the bark. 



GRINDING TAN-BARK, ETC. 185 

We have now quite a number of mills whioli reduce or break 
np the bark, and which are satisfactory to tanners. 

These mills are of various constructions: some grind the bark 
while others saw or cut it; in some the hoppers are straight^ in 
others they are wider at the top, while in others they are made 
wider in the middle than at their upper or lower ends. 

The stationary grinder was formerly generally made in one 
piece with the body of the hopper, and if any portion of the 
lower part was broken the entire hopper was useless and had 
to be replaced; but now the most exposed parts of the hopper 
and other portions of the mill are made in sections, and if one 
portion should be broken by excessive strain it can be readily 
replaced, while all the other parts may be retained. 

Some mills have an outwardly- convex rotating sieve to sep- 
arate the coarse from the fine bark, and transfer the former 
over the annular edges and a secondary grinding apparatus, in 
the form of a cylinder arranged under the ordinary mill and 
fastened to its shell. Those parts that are fine enough drop 
upon the rotating sieve and pass through the meshes. The 
coarse parts, however, are crushed between two sharp-toothed 
rings, of which the former is stationary, while the latter is fast- 
ened to the sieve and revolves with it. 

An improvement made on the Troy or Starbuck bark-mill in 
1869 consists in so arranging the grinders or graters in both the 
revolving and stationary parts of the mill one above the other, 
that the bark, coarsely ground by the upper, is discharged di- 
rectly into the lower grinding surfaces, where it is re-ground to 
the required fineness, and more evenly than was done prior to 
that date, when the bark required rehandling before being 
finished. 

Of late years the attention of inventors has been turned 
more to improvements in cutting mills than towards grinding 
mills for tan-bark. The horizonital, cylinder breaker bark- 
mill manufactured by C. Weston & Sons., Salem, Mass., is 
largely employed in the upper-leather tanneries of New Eng- 
land; it has a capacity of about two cords of bark per hour, 
and the price is |175. The present forms of grinding-mills 
used in sole-leather tanneries are mostly those upon which the 



186 



THE MANUFACTURE OF LEATHER. 



patents have long since expired ; but which have been slightly 
changed in regard to the fitting up, as, for instance, the mill 
shown (Figs. 16 to 19) has a safety coupling which was not em- 
ployed prior to 1875. 

The object of this safety device is to prevent breakage should 
a foreign substance get into it, and it is the invention of Mosser. 



Fig. 16. 



Fig. 17. 





Fig. 18. 



Fig. 19. 





jff JP 



Fig. 16 is a vertical section of the bark-mill. Fig. 17 is a 
top view. Fig. 18 is a detail top view of the runner. Fig. 19 
is a detail view of the inner surface of the lower part of a por- 
tion of the shell of the mill. 

A is the shaft, the lower end of which revolves in an oil-tight 
step in the bottom of the bowl B^ where it is supported adjusta- 



GEINDING TAN-BAEK, ETC. 187 

bly by a screw-pivot, (7, so that the mill may be readily changed 
to grind finer or coarser, as may be desired. 
■ Upon the upper edge of the bowl B are formed lugs to cor- 
respond with lugs upon the lower edge of the shell D^ and which 
are perforated to receive the bolts by which the shell and bowl 
are secured to each other. The lower part of the shell D is 
flared outward, or made somewhat bell-shaped, and in its inner 
surface is formed a ring-groove, into which are fitted toothed 
segments jE' of a ring-plate, which are secured in place by bolts 
F, passing through them and through the shell D. This con- 
struction brings the segments E to an inclination of about forty- 
five degrees. O is the runner, which is secured to the shaft A^ 
and is made in the shape of a concaved cone. 

In the lower edge of the runner G is formed a ring-groove to 
receive toothed segments H^ which are secured in place by bolts 
/, passing through the wall of the runner G. 

By this construction, should the toothed segments ^^ break 
or get dull, they can be readily detached and replaced by 
others. 

Around the upper edge of the shell D are formed lugs to cor- 
respond with lugs formed around the lower edge of the upper 
shell or hopper J", and which are perforated to receive the bolts 
by which they are secured together. Upon the inner surface 
of the upper part of the shell D are formed the outer ends of 
arms (7, the inner ends of which are formed upon a collar X, 
through which the shaft A passes. Upon the upper end of the 
shaft A is placed a breaker i/, Avhich is formed upon a long 
collar JV, through which is formed a square hole, so that its 
lower end may fit upon the square upper end of the shaft J., 
leaving its upper end empty to receive the square lower end of 
the driving-shaft. 

By this construction, the breaker J/ iV serves as a coupling, 
and should be of such a strength as to drive the runner G under 
ordinary circumstances; but should any hard substance get into 
the mill,, the collar iV will break, and thus prevent the mill from 
being broken. 

If desired, a breaker, (9, may be used without being provided 
with a coupling collar. 



188 



THE MANUFACTURE OF LEATHER. 



Upon the shell D, the shell or hopper J, and the runner G are 
formed teeth, projections, or flanges P, to break the bark into 
pieces before it passes to the toothed or grinding segments E H. 

The bark-mill shown in Figs. 20 and 21 is Barber's invention, 
and the novelty of it consists in providing the grinding or 
toothed segments with dovetail tenons, fitting into correspond- 
ing slots of the casing and wheel. 

Fisr. 20. 




Figure 20 is a detail vertical section of Barber's bark-mill. 
Fig. 21 is a detail top view of the running part of the mill. 

A is the driving-shaft, which revolves upon an adjustable 
pivot in a socket formed in the discharge-bowl B. Around the 
upper edge of the discharge-bowl B are formed lugs or a flange, 
C, upon which fit the lugs or flange i>, formed around the 
lower edge of the upper part or case E of the mill, so that the 
parts B E may be secured to each other by bolts F^ passing- 
through the ]ugs or flanges C D. 

The edges of the bowl B and case E should be rabbeted or 
halved to each other, so as to form a close joint even when the 
parts are not drawn closely together. 



GRINDING TAN-BARK, ETC. 



189 



The upper end of the case E is supported by the arms G^ the 
inner ends of which are connected with a collar, iT, through 
which the shaft A passes. 



Fig. 21. 




To the shaft J., just below the collar H^ is keyed the wheel 
or movable part /of the mill, which is made conical in its general 
form. To the upper part of the wheel / are attached radial 
cutters e/, to break or cut the bark into pieces as it is thrown 
into the mill. 

Upon the surfaces of the wheel / and case E are formed 
graduated flanges, cutters, or teeth K^ to still further break up 
the bark as it passes down to the toothed grinding-segments. 

Upon the inner side of the lower edge of the wheel / are 
formed lugs or a flange Z, to receive the bolts Ji", which also 
pass through the lugs or flange iV, formed upon the inner side 
of the upper edge of the ring 0, to fasten the said ring against 
the lower edge of the wheel /. 

The inner surface of the lower edge of the case E and the 
outer surface of the upper part of the ring have rabbets with 
inclined or dovetailed shoulders formed in them, which rab- 
bets, in connection with the edges of the discharge-bowl B and 



190 



THE MANUFACTURE OF LEATHER. 



ring 0, form dovetailed grooves to receive and clamp the 
toothed grinding-segments P. This construction enables the 
segments P to be made without any bolt-holes through them, 
and with their ends fitted against each other, so that there will 
be no cavities and interstices into which wet bark may stick 
and form a nucleus of a collection that will finally clog the 
mill. This construction also enables the grinding-segments to 
be readily taken out when worn or broken and replaced with 
others. 

The invention shown in Figs. 22 to 30 relates to machines 
having rotary cutters for cutting or reducing bark for tanners' 
use ; and it has for its object, first, to provide certain improve- 
ments in the rotary cutter, whereby the machine is enabled to 
run at a lower rate of speed and with less wear and jar than 
heretofore ; secondly, to provide improved means for separating 
coarse fragments of bark from the properly-reduced particles ; 
thirdly, to enable the cutter to be readily exposed or uncovered 
when desired. 



Fiff. 22. 



Fig. 23 




Figure 22 represents a side elevation of a bark-cutting 
machine embodying the invention. Fig. 23 represents a trans- 
verse vertical section of the same. Fig. 24 represents a modifi- 
cation. Fig. 25 represents a section on line x x. Fig. 23. Fig. 



GRINDING TAN-BARK, ETC., 191 

Fig- 24. Fig. 25. 




Fig. 26. 



^ 


ijiiij 


1 1 


■) 


iiin.,..„,. 




p 


hf'' 




=^1 




•ii 


lilf'^ 


^"~3 


fe^ 




^\i\-m 


r*- 


Hi 


llW 




riUI 




ill 


i 


(O/ 


.... 




1 


~j 


^SL— 




1^' 1 III Jill 




Ei 


[1!^^ 




ojlll jlH 


ill 


nj 


^. 




W\ "1 




Hi 


Ik 






ill 


J 


ja/ 








1 


a- 





i^' 1 III liiii 


i 


uiil 


Ik 








ill 


1 


^ 




w^ 1 




z. 




11 


*, iiiii 








Fig. 27. 



Fi-. 28. 





26 represents a plan view of the rotary cutter. Fig. 27 repre- 
sents a section on line y ?/, Fig. 26. Fig. 28 represents a front 
view of the machine. Fig. 29 represents a side view with the 



192 



THE MANUFACTURE OF LEATHER. 



hojDper turned back to expose the cutter. Fig. 30 represents 
a side view of the hopper detached. 

In the drawings, A represents the rotary cutter, constituting 
a part of the invention. This cutter is composed of a cylindri- 
cal body and independent teeth a a', projecting therefrom, the 
cutter being preferably formed by placing a series of saws side 



Fi^. 29. 



Fiff. 30. 




by side on an ai'bor, although any other suitable construction 
may be adopted. The teeth a a' are shaped like the teeth of 
an ordinary circular saw, and the teeth a are longer — that is, 
their points project farther from the axis of the cutter than the 
points of the teeth a', the difference in length being preferably 
about one eighth of an inch. The teeth are arranged in rows 
extending longitudinally of the body of the cutter, each longi- 
tudinal row being composed of alternating longer and shorter 
teeth, as shown in Fig. 26. The teeth forming the longitudinal 
rows are placed side by side, each in contact with the next, so 
that there are no vacant spaces between them ; hence the longi- 
tudinal rows are continuous. The teeth are also arranged in 
rows extending around the periphery of the cutter, the teeth of 
each saw constituting a peripheral row. It is preferable to 
make these peripheral rows of alternating longer and shorter 
teeth, as shown in Figs. 26 and 27. By this arrangement of 
teeth each tooth is enabled to separate an independent fragment 
from a sheet or piece of bark, and no part of the end of the bark 



GRINDING TAN-BARK, ETC, 19S 

is left untouched by each longitudinal row, as would be the 
case if the teeth were separated by intervening spaces, as has 
been usual heretofore. When the teeth are so separated the 
cutter has to be driven very rapidly, in order that the portions 
of the bark untouched by one row of teeth may be properly 
cut by the succeeding rows, and unless the cutter is driven very 
rapidly its tendency is to break or crush off the tongues left on 
the end of the bark by the vacant spaces between the preceding 
teeth, the result being the detachment of fragments too large to 
be properly leached and the reduction of a portion of the bark 
to powder, which is always objectionable in the reduced bark, 
because it accumulates in masses and resists the action of water 
in leaching. 

This cutter does not require to be driven so rapidly as those 
heretofore used, so that less power is required to drive it and 
less jar and vibration are caused by the operation of the 
machine. 

The arbor of the cutter is supported in suitable bearings on 
the top of a supporting-frame, B^ which incloses a chute, C\ 
below the cutter. In this chute is located a shaft, D, journaled 
in a movable frame, E^ which is adapted to slide into and out 
of the frame B. 

The shaft D is provided with a series of peripheral collars, 
F^ and intervening peripheral grooves or pockets, 6^, about half 
an inch wide, and having partitions H H. The interior of the 
frame E forms a part of the chute C^ and is about equal in 
width to the diameter of the collars, so that when pieces of bark 
too large to enter the pockets G fall from the cutter they will 
be arrested by the collars, the properly-reduced cuttings falling 
into the pockets G^ and being carried over by the partitions H^ 
as the shaft revolves. 

The pieces arrested by the collars F may be cut or broken 
up by the joint action of teeth /, formed on these collars, and a 
shoulder, «/, formed on one of the side blocks of the frame E^ 
this shoulder having grooves K^ through which the collars pass. 
The pieces of bark are arrested by the shoulder e/, while the 
teeth / cut or break them. If desired, however, the shoulder 
«/, and teeth /, may be dispensed with and the shaft Z> may be 
13 



194 THE MANUFACTUKE OF LEATHER. 

located nearer the cutter, so that pieces of bark arrested by the 
collars i^ will be caught up by the cutter, as they accumulate, 
and carried over by it to the bed-plate, hereafter described, to 
be reduced, 

JV represents what we will term the "hopper-frame," which 
is located at the top of the frame i?, and is provided with lugs 
P, extending downwardly and pivoted at to the frame B. 
This frame incloses and covers the cutter when in operative 
position, and has the general form of a hopper. One side of 
the frame is inclined and properly arranged with reference to 
the cutter to constitute a bed-plate, Q, to support the bark as it 
is presented to the cutter. This bed plate does not extend in 
one piece to the cutter, but is supplemented by a movable steel 
plate, a. Two methods of supporting and moving the plate H 
are shown, respectively, in Figs. 23 and 24. In the former 
the plate H is attached to an inclined plate, *S', which forms a 
part of the frame B. The plate i?, in this case, is at right 
angles with the bed-plate, and is attached to the plate S^ by a 
bolt, T^ passing through a slot in the plate B. Screws F, pass- 
ing through a flange, TF, on the plate S, serve to move the 
plate i? at right angles to the plane of the bed-plate when the 
bolt T is lowered. 

In Fig. 24 the plate li is attached by a bolt, T'^ to an inclined 
plate, S', forming a part of the frame B. The bolt T' is at- 
tached to the plate JR, and passes through a slot in the plate S'. 
In this case the plate M is movable in the same plane as the 
bed-plate. In either case the plate jR constitutes an adjustable 
terminus of the bed-plate, which receives the wear caused by 
the action of the cutter on the bark, and is capable of being ad- 
justed to compensate for wear. 

The hopper-frame N is provided with a feed-roll, C/, which 
is positively rotated by a sprocket-wheel, i\''', connected by a 
chain, N^, to a wheel, iV^, which is journaled on a shaft, N*, 
projecting from a plate, iV^ attached to the side of the hopper- 
frame. The feed-roll U is journaled in weighted arms U' U', 
which are pivoted at u w, to the sides of the hopper-frame, and 
are adapted to oscillate and permit the feed-roll to move laterally. 

By pivoting the hopper-frame to the supporting-frame B^ as 



GRINDING TAN-BARK, ETC. 195 

described, and supporting the feed-roll and its driving mechan- 
ism on' the hopper-frame, it is possible to readily expose the 
cutter by swinging back the hopper-frame, as shown in Fig. 29, 
whenever the cutter is to be removed or repaired, thus avoid- 
ing the labor and delay usually incident to removing the hop- 
per and other mechanism to enable access to be had to the 
cutter. 

The shaft of the feed-roll projects through slots C^, in the 
sides of the hopper. The sides of the hopper have vertical 
openings U^^ extending from the slots ?7^, to permit the upward 
movement of the shaft of the feed-roll when it is desired to 
remove the latter. The openings ?7^, are closed when the feed- 
roll is in place by pieces TT^, attached to the cover T/^, of the 
hopper, said cover being detachable with the pieces U^. 

F' represents a friction-roll located in an opening in the bed- 
plate. 

This invention is No. 229,205, mentioned on p. 197. 

List of all Patents for Bark Mills issued hy the Government of the 
United States of America, from 1790 to 1883 inclusive. 

1^0. Date. Inventoi'. Residence. 

July 19, 1794, J. Markley, 

Mar. 17, 1802, J. Warrel, 

May 21, 1805, T. W. Prior, ' Philadelphia, Pa. 

May 7, 1807, C. Tobey, Hudson, N. Y. 

Mar. 18, 1808, 0. Pease aud Norwalk, Conn. 

A. Donalds, 

Mar. 20, 1811, L. Gale, Berkshire, Co., Mass. 

Jnly 16, 1813, C. Churchman and Upper Chichester, Pa. 

G. Martin, Jr. 

April 18, 1814, J. Olds, Meriden, Conn. 

May 16, 1815, L. Gale, Lenox, Mass. 

Oct. 31, 1820, N. Sears, Hudson, N. Y. 

Nov. 22, 1821, E. and J. Trask, Sangerfield, N. Y. 

May 24, 1822, J. Elliott, Philadelphia, Pa. 

April 11, 1825, H. Haiglit, Jr., and Stamford, Conn. 

H. White, 

Oct. 25, 1826, C. Foss, Madison, 0. 

Sept. 13, 1827, W. Tarry, Westbrook, Me. 

Mar. 27, 1828, A. Bull, Caroline, N. Y. 

May 29, 1828, J. Montgomery, Sangerfield, N. Y. 

Feb. 1, 1830, M. Hurd, Augusta, N. Y. 

May 3, 1831, M. Hurd, Augusta, N. Y. 



196 



THE MAXUFACTURE OF LEATHER. 



No. 


Date. 


luventor. 


Residence. 




Sept. 30 


1831, 


C. H. Green and 
R. Montgomery, 


Sangerfield, N. Y. 




Feb. 27 


1832, 


J. T. Gilford, 


Veteran, N. Y. 




Mar. 27 


1832, 


D. Humberd and 
G. Downs, 


McConnelsville, Pa. 




April 17 


1833, 


J. Trask, A. Seabury, 
and W. Young, 


Sangerfield, N. Y. 


484 


Nov. 25, 


1837, 


C. Parker, 


Meriden, Conn. 


532 


Dec. 26, 


1837, 


A. McMillen, 


Bedford, N. H. 


1,714 


Aug. 12 


1840, 


R, Montgomery and 
L. W. Harris, 


Sangerfield, N. Y. 


2,716 


July 11 


1842, 


V. Birely, 


Frederick, Md. 


2,944 


Feb. 4 


1843, 


B. R. Beardsley, 


Sangerfield, N. Y. 


3,767 


Sept. 27, 


1844, 


M. Beeclier, 


Remson, N. Y. 


4,090 


June 25, 


1845, 


A. P. Norton and 
M. Owen, 


Sangerfield, N. Y. 


4,237 


Oct. 25 


1845, 


J. Scudder, 


Plattsville, N.Y. 


4,335 


Dec. 26, 


1845, 


A. Lindsey, 


Canton, Me. 


6,916 

Reissue 

180 


^Dec. 4, 
J Oct. 15, 


1849. 
1850. 


S. A. Bant and 
W. Andrew, 


i Frederick, Md. 


12,487 


Mar. 6 


1855. 


S. W, Powell 


Tuscarora Valley, Pa. 


20,692 


June 29 


, 1858. 


B. R. Beardsley, 


Waterville, N. Y. 


28,518 


May 29 


1860, 


W. Tansley, 


Salisbury Centre, N. Y 


28,5.54 


June 5 


1860. 


J. Brakely, 


New York, N. Y. ■ 


42,811 


May 17, 


1864, 


M. Winger, 


Ephratah, Pa. 


44,756 


Oct. 18 


1864, 


W. Tansley, 


Salisbury Centre, N. Y 


49,319 


Aug. 8, 


1865, 


N. S. Thomas, 


Painted Post, N.Y. 


85,172 


Dec. 22, 


1868, 


B. Irving, 


New York, N.Y. 


86,675 


Feb. 9, 


1869, 


B. Irving, 


New York, N. Y. 


97,989 


Dec. 14 


1869, 


W. Tansley, 


Salisbury Centre, N. Y 


101,984 


April 19 


1870, 


J. G. Curtis, 


Emporium, Pa. 


103,246 


May 17 


1870, 


R. H. Shultis, 


EUenville, N. Y. 


103,881 


June 7 


1870, 


L. H. Hermance, 


Kingston, N.Y. 


107,923 


Oct. 4 


1870, 


C. Korn, 


Wortsborough, N. Y. 


111,239 


Jan. 24, 


1871, 


G. E. Palen and 
F. P. Avery, 


Tunkhannock, Pa. 


111,397 


Jan. 31 


1871, 


F. Stamm, 


East Lampeter, Pa. 


111,744 


Feb. 14 


1871, 


J. Helenbrook, 


Clean, N. Y. 


120,246 

Reissue 

7,143 


)0ct. 24 
)May 30 


1871. 

1876. 


> 0. Coogan, 


Pittsfield, Mass. 


153,492 


July 28 


1874, 


J. Moulton, 


Ossipee, N. H. 


176,709 


April 25 


1876, 


S. R. Thompson, 


Portsmouth, N. H. 


179,401 


July 4 


1876, 


0. Coogan, 


Pittsfield, Mass. 


190,182 


May 1 


1877, 


W. H. Barber, 


AUentown, Pa. 



GEINDING TAN BARK, ETC. 197 



No. 




Date 




Inventoi-. 


Residence. 


190,777 


May- 


15, 


1877, 


W. F. Mosser, 


Allentown, Pa. 


198,614 


Dec. 


25, 


1877. 


C. P. Hayes, 


Brooklyn, N. Y. 


200,361 


Feb. 


12, 


1878, 


S. R. Thompson, 


Brookline, Mass. 


201,938 


April 


^ 2, 


1878, 


W. E. Nickerson, 


Somerville, Mass. 


206,494 


July 


30, 


1878, 


R. H. Shultis, 


Kingston, N. Y. 


210,095 


Nov. 


19, 


1878, 


W. Chicken, 


Chelsea, Mass. 


211,666 


Jan. 


28, 


1879, 


W. E. Nickerson, 


Somerville, Mass. 


211,798 


Jan. 


28, 


1879, 


Wm. Shaw, 


Kingman, Me. 


220,274 


Oct. 


9, 


1879, 


Wm. Chicken, 


Chelsea, Mass. 


220,945 


Oct. 


28, 


1879, 


C. P. Ryther, 


Carthage, N. Y. 


221,870 


Nov. 


18, 


1879, 


Wm. Shaw, 


Kingman, Me. 


229,205 


June 


22, 


1880, 


S. R. Thompson, 
S. W. Johnson, 


Brookline, Mass. 
West Medford, Mass, 


234,324 


Nov. 


9, 


1880, 


D. Obrien 


Oswayo, Pa. 


238,923 


Mar. 


15, 


1881, 


S. Kiillman, 


San, Francisco, Cal. 


249,825 


Sept. 


13, 


1881, 


W. Chicken, 


Chelsea, Mass. 


264,152 


Sept. 


12, 


1882, 


J. C. Hagerty, 


Santa Crnz, Cal. 


282,771 


Aug. 


7, 


1883, 


L. F, Reed, 


Hornellsville, N. Y. 



Process for preparing Tan-baric for use.^ which consists in crushing 
the Dry Barh and reducing it to thin flakes by passing it 
between rollers under heavy pressure after it has been ground. 

It is well known to those engaged in tanning that it is diffi- 
cult to extract all the tannin from bark when used in the ordi- 
nary way in tanneries ; and as tan-bark is becoming constantly 
more difficult to obtaiii in the required quantities, and conse- 
quently more expensive, it is very desirable to have some 
means by which the tannin may be more effectually, and also 
more quickly, extracted from the bark, and to accomplish this 
is the object of the present invention. Ordinarily the bark is 
simply ground in a bark-mill, and then leached in vats ; but 
when so used the cellular structure of the bark is not destroyed 
or broken up, and the consequence is that, even though the 
bark be leached for a long time, more or less of the tannin is 
still retained in the cells of the bark, and is thereby lost. 

In Figs. 31 and 82 there is illustrated a simple form of 
machine for breaking up the cellular structure of bark, invented 
by Mr. Byron Holbrook, of Kenosha, Wisconsin. 

Fig. 31 is a perspective view and Fig. 32 a transverse verti- 
cal section of a machine designed for treating bark in accord- 
ance with this method. The machine consists of the rollers, A 



198 



THE MANUFACTURE OF LEATHER. 



and B^ mounted in a suitable frame, the roller B being mounted 
in fixed bearings, while the roller A is mounted in adjustable 



Fig. 31. 




Fisr. 32. 




bearings, having set-screws, <?, or equivalent means for regulating 
the pressure at will. These rollers carry at one end gear-wheels, 
C Z), while the roller A has at its opposite end a gear-wheel, (x, 



GRINDING TAN-BARK, ETC. 199 

with whicli engages a pinion, /, secured to a counter-shaft, i7, 
which carries at its opposite end a pulley, «/, to receive a belt 
from the engine or driving shaft, and by which motion is im- 
parted to the two rollers. A wheel, E^ is secured to the oppo- 
site end of roller B\ and arranged to engage with a wheel, F^ 
secured to the end of a feed shaft, L, which extends lengthwise 
through a hopper, i/", secured above the rollers, as shown 
in Figs. 31 and 32. One of the rollers, J., is provided at each 
end with a radial flange, c, which fits into a corresponding recess 
on the ends of the roller, .5, the object of which is to prevent 
the bark from working or being crowded out from between the 
rollers at their ends. Underneath each roller is arranged a 
scraper, T^ which extends the entire length of the face of the 
roller for the purpose of removing all adhering particles of bark 
and gummy matter, with which they would otherwise soon 
become coated. These scrapers may be made adjustable. 

As shown in Fig. 32, the feed-shaft consists of a rectangular 
metallic bar, the angles of which, as it revolves, force the bark 
between the rollers Avith a constant and uniform motion. If 
preferred, a ribbed roller may be used for this purpose. The 
rollers are shown so geared that they will revolve with uniform 
speed; but it is obvious that they may be arranged to rotate at 
different velocities, and the inventor proposes to so use them, 
especially when three or more rolls are used together, the more 
rapidly rotating roller having the effect of tearing or pulling 
the fibre asunder, thus tending to disintegrate as well as to 
compress and crush the bark. It is preferable to use rollers of 
comparatively small diameter, for the reason that they will ope- 
rate more effectually, as only a smaller portion of their surfaces 
will act at any one instant upon the bark that may be between 
them. 

In preparing the bark it is generally first ground in a bark- 
mill in the usual manner, and then passed between the rollers in 
the manner described, care being observed to have the rollers 
so adjusted as to apply a very strong pressure to the particles 
of bark as they pass between them. The bark will pass from 
the rollers in the form of a thin sheet or thin flakes, with its 
cellular structure completely broken up or destroyed,- so that it 



200 THE MANUFACTURE OF LEATHER. 

is claimed to be in a condition to readily yield up its tannin far 
more effectually, and in much less time than when prepared in 
the ordinary manner or merely ground. 

Section II. Improved Bark- Conveyer. 

This invention, which was patented May 1, 1883, by Mr. 
Oliver A. Zane, of Peabody, Massachusetts, relates to the end- 
less chains and lags or devices connected therewith for convey- 
ing bark or various other matters from one position to another, 
it being specially useful for what in tanneries are termed 
" ground-bark conveyers," each of which in the main consists of 
an endless chain and a series of lags or bars, such lags or bars 
being arranged at equal distances apart and fixed or held to the 
chain, and the latter being extended around and supported by 
two spider or sprocket wheels. The conveyer so constructed is 
arranged to extend within a trough, through which, lengthwise 
of it, the chain in moving drags the lags and causes them to force 
along with them the bark or material to be transferred from one 
position to another or higher one. 

Fig. 33 is a top view. Fig. 34 a longitudinal section, Fig. 35 a 
side view, and Fig. 36 a transverse section, of part of a conveyer 
containing Zane's improvement. Fig. 37 is an edge view of 
one of the links of the endless chain of such conveyer. Fig. 38 
is a rear elevation, and Fig. 39 a front elevation, of one of the 
lags of the conveyer. 

Previous to this invention it had been customary to construct 
certain links of the chain with ears extending from them and 
formed as shown in Figs. 40 and 41 at a a, the lag being fast- 
ened to the link by screws passing through the ears. These 
ears are very liable to become broken from the link, and 
thereby render it useless, and to necessitate the substitution of 
another, frequently at considerable expense, inconvenience, or 
loss to the tanner. With this invention the links of the chain 
are all alike and require no such means of connection of any of 
them with a lag, which may be attached to any one of them- 
throughout the chain. In Figs. 33, 34, 35, and 36, these links 
are shown at A A A and a lag at B. Each link tapers lengthwise 



GRINDING, TAN-BARK, ETC. 
Fig. 33. 




Fig. 34. 




Fig. 35. 




Fig. 36. 




Fig. 38. 



Fig. 39. 



7 ^ V 



} 



Fig. 41. 



^^^^ 



Fig. 37. 




201 




Fig. 40. 




and crosswise; or, in other words, it is not only dovetailed in 
form lengthwise of it, but is also dovetailed transversely of it, as 
represented. It is hooked, as shown at c, at one end to clasp the 



202 THE MANUFACTUEE OF LEATHER. 

cylindrical end part, cZ, of the next link, each link being notched 
as shown at e and g^ to enable it to be coupled with or uncoup- 
led from another link. The lag B has made in it a notch or re- 
cess, /, to receive a link, such notch or recess being tapering or 
dovetailed both lengthwise and transversely of it to receive and 
fit to a link, which, previous to being engaged with its two 
next adjacent links, between which it is to extend, is to be 
placed within the notch or recess. Instead of this double dove- 
tailed notch or recess being formed immediately within the bap 
or lag, it may be in a block or piece of metal screwed or fast- 
ened to the lag. While the dovetails of the link will keep the 
lag from slipping off the link in one direction transversely and 
in another lengthwise of it, the next link, by extending trans- 
versely beyond the lag-link, as shown, will prevent the lag from 
slipping off its link in the opposite direction longitudinally of 
the link. Thus by having to the lag a double dovetailed recess 
or link-socket, as described, and by having the chain-links made 
as represented, it is possible not only to readily adapt a lag to 
any link of the chain, but also to keep it in place without any 
screws, ears, or other fastenings, as heretofore employed; and 
when a tanner is provided with auxiliary'- links he can, in case 
of breakage of any one of the chains, readily supply its place 
with another. 

Instead of a lag, a bucket may be used, and be provided with 
a double dovetailed recess or link-socket, as described, to 
receive a link of the chain. 



LEACHING TAN-BARK. 203 



CHAPTER XII. 

LEACHING- TAN-BARK— THE KINDS OF LEACHES EMPLOYED — 
BUILDING ROUND LEACHES — FILLING AND RUNNING THE 
SPRINKLER LEACHES — THE " BARKOMETER" — PURIFYING EX- 
TRACTS OF BARK — OBTAINING TANNIC ACID IN ACICULAR 
FORM — LIST OF AMERICAN PATENTS FOR PROCESSES AND 
APPARATUSES FOR LEACHING AND MAKING EXTRACTS OF 
TAN-BARK. 

Section I. The Kinds of Leaches Employed. 

The best method for leaching or extracting the tannin in a 
perfect state, from tan-bark, has been for a long period eagerly 
sought after by tanners, and at the present time we have a 
great number of ways for performing this operation ; in some of 
which sulphuric acid, blood, electricity, etc., are the active 
agents, but the usual manner employed by tanners is to remove 
the desired soluble portion of the ground bark by filtering, 
using water as a solvent. 

The lixiviation is commonly conducted by one of three 
methods : in vats of various forms, but generally they are either 
round or square, and by one system the water is forced through 
the ground bark either from the bottom or the top by pressure 
obtained sometimes from a tank placed above the leaching vat, 
the altitude of which regulates the intensity of the pressure. 

In a second method the tannin is extracted by forming 
a nest of leaches or placing one above the other, and then 
heating the bark and liquor contained in the top leach, and 
allowing the liquor to fall upon the lower leaches, and thus the 
bark is saturated and allowed for a time to remain stationary. 

The third form, and the one now usually employed in all 
large tanneries in this country, is termed the sprinkler leach, 
which manner of leaching was invented by Messrs. Allen and 



204 THE MANUFACTURE OF LEATHER. 

Warren in 1862, and by this method the water is made to per- 
colate through the bark. 

In the first mode the leaches are commonly divided into sets, 
and the number of leaches in a set accords with the working 
days of the week, and one fresh leach of each set is filled each 
day, and the heat is usually applied only to the back or weak- 
est leach, thus allowing the strong liquor when it enters on the 
head leach of the set to be in a comparatively cold state, and 
thus leaving a large amount of impurities behind when it goes 
upon the leather in the yard from the head leach without 
further cooling. 

Leaches of this kind may be constructed of either square or 
round form; but the square is best when placed in the ground, and 
then they should be on a level, and faithfully filled around "with 
clay or loam, and should be in area 6x6, 8x8, 10x10, 12x12, or 
14x14 feet, etc., but when the leaches are to be placed above 
ground, the round form is best; the size of the vats in the tan- 
yard regulating the capacity. 

The best material from which to construct leaches of this kind 
is pine or hemlock plank of good thickness, which should not be 
less than two inches, and the planks should be well battened 
together and corked. 

The second form or " douse" leach may be either round or 
square of any size, and it may be filled with bark and the li- 
quor, or water run on, or the bark may be run on with the liquor 
by floating it from the mill, and the heat for this form of leach 
may be applied in any of the usual ways, either by inserting 
steam under the false bottom, or if it is desired, the water or 
liquor may be heated previous to running it on. But as by 
this method the liquors in the yard are diluted, it should be 
avoided in heavy tannage, and this is not generally considered 
by our best tanners to be so satisfactory, as either the press or 
sprinkler methods. 

The Allen & Warren sprinkler is only applicable to round 
leaches, but there are other forms of sprinklers which leach the 
bark in vessels irrespective of their shape. 

The object of the invention shown in Figs. 42 to 45 is to pro- 
vide an apparatus for the automatic distribution of fluids for 



LEACHING TAN-BARK. 205 

leaching, and to render such distribution uniform over the sur- 
face of the material ; while at the same time providing means 
for regulating the quantity of the fluid so distributed without 
decreasing the head pressure, velocity of flow, or speed of the 
distributing apparatus, and to render such distribution of the 
fluids uniform without regard to the shape of the leaching-ves- 
sel. These are the distinctive features of the invention, which 
consists in laying the fluid in a thin unbroken sheet, increasing 
in quantity in proportion to its distance from the axis of rota- 
tion, by means of fissures made in the opposite sides of the 
distributing-arms, and increasing in width toward their outer 
ends, while the outlet capacity of these distributers can be 
increased or diminished, and the volume thereby regulated 
without any change in the pressure, the velocity of the dis- 
charge, or in speed of the apparatus. The invention, which is 
that of Johnson, also consists in the combination, with auto- 
matic-distributing arms, of automatic gates or valves at the 
ends thereof, operating to open vents or fissures, at stated inter- 
vals during the revolving motion of the arms, for the purpose 
of projecting the fluid over an increased area of the leaching- 
vessel, such as the spaces formed by the corners of a square or 
many-sided vessel. Thus there is effected an equal distribution 
of the water or fluid over the whole surface of the material 
without regard to the shape of the vat ; the opening of the 
gates being, of course, governed by the shape of the vat, and 
the means for effecting their opening being also made to con- 
form to the movement of the gates. 

Fig. 42 represents an elevation of a sprinkler for leaching, 
embracing this invention ; Fig. 43 a plan thereof, showing the 
application to a square tub; Fig. 44 an end view ; and Fig. 45 
a cross section. 

The sprinkler consists of two revolving hollow arms, a, of 
thin metal, suspended by a loose joint, 5, from a fixed conduit, 
c, leading from the head or reservoir. These arms extend equi- 
distant from the conduit, and are split to form narrow openings 
or fissures, dd^ on opposite sides from which the fluid issues in 
thin sheets, and by its action causes the arms to revolve, dis- 
charging the leaching-fluid into the vat ; and in order that this 



206 



THE MANUFACTURE OF LEATHEU. 
Fig. 42. 




Fis. 43. 



Fig. 44. 



Fig. 45. 




CL- 




LEACHING TAN-BAEK. 207 

discbarge may be uniform, and in proportion to the increasing 
area of the tub from the centre, these fissures are made to 
gradually increase in width from the conduit to tlie ends of the 
arms, as shown in Fig. 42. To increase or diminish tlie width 
of the distributing-fissures, the inventor employs adjusting- 
screws, e, passing vertically through the hollow arms, being 
riveted therein at their lower ends, and provided with thumb- 
nuts/, at their upper projecting ends, so as to bear upon the 
upper section of the split tube, and draw the sections together, 
or allow them to open as the nuts f are turned, the arms for 
that purpose having sufficient spring. These adjusting screws 
are arranged at such intervals as to effect the desired width 
of the discharging-fissures. Instead of having the adjusting- 
screws to pass through the arms, they may be embraced by 
yokes e', through the upper ends of which the screws e pass, so 
as to bear upon the upper side of the arms. By this means 
the fluid sheet is increased or diminished in thickness, or 
volume uninterruptedly from the centre to the extremities of 
the arms, and the material is thereby evenly and uniformly 
sprayed in proportion to its increased bulk from the centre of 
the tub, which is a matter of vital importance, to effect a uni- 
form degree of leaching by percolation. In connection with 
the automatic continuous distribution of the fluid from the 
arms, the inventor also employs gates or valves, g, at the ends 
thereof, which are operated automatically at stated intervals to 
open fissures or jets to project sheets or streams of the fluid 
from the ends of the arms to sprinkle the angular spaces formed 
by square or many-sided vats. These end streams may be pro- 
jected in the line of the arms or obliquely thereto, and the gates 
may be arranged to work in the ends of the arms in any suita- 
ble way to accomplish this purpose. In the drawings they are 
arranged to slide vertically in guides formed in heads 7i, on the 
ends of the pipes, and to open and close the end fissures g^ by 
means of levers, ^, connected with said gates, pivoted to short 
posts, j, on the arms, and connected to and operated by a serpen- 
tine cam, K, fixed to the lower end of the conduit, so that the 
revolving motion of the arms will carry the inner ends of 
the levers over the cam, and thereby cause the vibration of 



208 



THE MANUFACTUEE OF LEATHER. 



the levers, and the automatic opening and closing of the end 
gates. 

The sinuosities of the cam must, of coarse, be made to conform 
to the frequency with which the gates are desired to be opened. 

This sprinkler is by its construction adapted for use with 
either round or square vats, the only requirement for such 
change being the removal or attachment of the valve-operating 
levers, as with round vats the valves serve as closed ends to 
the arras. 

Formerly two kinds of the sprinkler leach, the "centre post 
sprinkler" and " the hanging sprinkler," were in use, but the 
latter has almost entirely superseded the former arrangement. 

Fig. 46. 




I' 



trl L ri~rT i_ _— ; 

intTTTri 








In the Allen & Warren sprinkler the perforations gradu- 
ally increase in size as they approach the edge of the leach, thus 
allowing a uniform distribution of the leaching fluid to be dis- 
tributed over the entire surface of the bark. 

The patent on the Allen & Warren sprinkler has now ex- 
pired. 

Fig. 46 shows a perspective view of a leach having the Allen 
& Warren "hanging sprinkler," the leach A is of the same 



LEACHING TAN-BARK. 209 

diameter at both top and bottom, the sprinkler B is of brass, and 
the holes in which are so adjusted as to furnish water or liquor 
uniformly to the entire surface of the bark in the leach, the pres- 
sure of the liquid maintains the sprinkler in motion, and the flow 
of liquor or water to the sprinkler is regulated by a valve. 

The water or liquor is continually pressing and passing 
down in every part of the tub ; and as the sprinkler is made to 
distribute steadily to every part of the bark an equal amount of 
leaching fluid, the strength is taken from the bark uniformly. 

Section II. Building Bound Leaches. 

In building these round leaches pine lumber is the best to 
employ, but hemlock, spruce, or oak will answer very well, 
especially when the tubs are to be well sheltered. It should be 
partially seasoned — neither green nor quite dry. Use two-inch 
plank for the bottom and sides ; it is not necessary to use thicker. 

There is no need of matching or dowelling, as a good square 
joint can be made as impervious to water as the lumber itself, 
and without calking. 

Commence by selecting a plank an inch longer than the 
interior diameter of the tub ; make the centre of this the centre 
of bottom of leach, and with cir.cling-stick begin to mark out 
the circle ; continue to mark as the planks are, one after an- 
other, jointed and put in place, to guard against waste of lumber. 
When all needed planks are placed, apply a " set," and draw 
the whole well together. The joints should be made a little 
open across the centre, so that the " set" will bring the planks 
up to a good square joint; otherwise the joints will be open 
towards the ends. Screw board cleats on, withdraw the " set," 
strike a perfect circle, and cut it out. With gauge and plane 
make the bottom of one thickness at the edge. The cleats are 
to be taken off before the tub is finished. 

The length of the staves or planks for the sides, should be 
ten inches more than the desired depth of tub above the false 
bottom ; their width should not exceed eight inches for a leach 
ten feet in diameter, nor twelve inches for one sixteen feet in 
diameter. 
14 



210 THE MANUFACTURE OF LEATHER. 

Cut all the planks to the proper length first ; number them, 
and lay them side by side in convenient portions ; tack on a 
straight edge, and plane a groove or croze, one half inch deep, 
and of sufficient width to admit the bottom ; the groove should 
be three inches from the end of the staves. 

Take two pieces of plank about four feet long, and cut in each 
a segment of a circle of the same radius as the outside of the 
leach, and set them nearly the length as the staves apart. (See 
Fig. 4:7.) Joint the staves in these forms, take plank number 

Fis. 47. 




3 



one, and bevel the edges slightly; bevel plank number two, 
to make close joint with number one ; fit number three to num- 
ber two, and so on until all the staves are fitted. In this way 
a perfectly round tub is secured. Eitiier a saw or plane can 
properly be used to bevel the edges. The groove in the staves 
should be rounded out slightly, to conform to the circle of 
bottom of tub. 

Having prepared a good foundation, place the tub bottom on 
it. Then set the staves up as numbered, and temporarily secure 
them to the bottom by a nail or two through each, at the 
crozing. , 

When wooden yokes are used to hold the hoops in place, 
they should be of hard wood, about three by six inches, and the 
length of the leach-staves. For a tub fifteen feet or less in 
diameter, two yokes are enough ; for a larger tub, three yokes 
are recommended ; to be placed at equal distances. The holes 
for the hoops should be bored so as to admit them at the edge 
of the tub, otherwise the hoops will force in the yokes so as to 
press the leach out of round. 




LEACHING TAN-BARK. 211 

Fig. 48 represents a cast iron yoke well adapted to take tlie 
place of the wooden one ; it is hollow, and is quite light. The 
following is a good size : Length at the base, 
5 inches; at the top, 3f inches; width and l^'ig- 48. 

height, 2| inches. 

Four hoops for leaches 14 feet and less in 
diameter, and five hoops for larger tubs, are 
advisable. The lower third of the tub will 
have to resist quite as great pressure as the upper two-thirds, 
and the hoops should be placed accordingly. Thus, when 
boring the yokes for four hoops, have one six inches from the 
top, and another six inches from the bottom of the staves, a 
third midway from top to bottom, and the fourth half way from 
the central hoop to the bottom of the staves. Use |-inch and 
f-inch round iron for the hoops, the larger size for leaches over 
13 feet. It is found most convenient, without increasing ex- 
pense, to make the hoops in parts, as shown in Fig. 49. A hook 

Fiff. 49. 




on one end of the short-threaded piece which passes through 
the yoke is inserted into a similar hook, or an eye, of the long 
semi-circular hoop which connects the yokes. 

To complete the tub, the threaded ends of the short pieces of 
round iron are thrust through the yokes, the washers and nuts 
are put on, the yokes placed against the tub and connected by 
means of the longer parts of the hoops, and the whole drawn in 
place with nut and wrench. 

The simplest, and a very good, false bottom is made of a sin- 
gle thickness of one and one-fourth inch narrow boards, placed 
about one-quarter of an inch apart, and the edges slightly 
bevelled, so the opening shall be slightly larger on the under 
side. 

Another way, which requires a little more care and lumber 
in construction, is to lap one-inch rough boards, six or eight 



212 THE MANUFACTURE OF LEATHER. 

inches in width, as shown in Fig. 50. The upper boards are 
placed about one inch apart, the under boards about two inches 
apart. Scantling, two inches by three, should be laid at inter- 
vals of twelve to eighteen inches, to support the false bottom, 
which will thus be three inches above the true bottom. The 
scantling should be notched on the under side to admit the free 
passage of liquors. 

Fiff. 50. 



A substantial flooring about the leaches, near the top, is 
always useful. Whenever, through careless work, the tops of 
the leaches are liable to get out of round, a flooring will keep 
them in form. 

To find the capacity, in cubic feet, of a round leach of any 
size, multiply the square of the diameter in feet by the decimal 
.7854, and the product by the depth in feet, and to find the 
capacity in cords divide this product by 128. For example: 
A tub 12 feet in diameter and 6 feet deep will hold 12 x 12 X 
.7854 X 6 = 678.5856 cubic feet = 5.3 cords. 

The following table shows the capacity of round leaches of 
many sizes. The exhibit of material and labor needed in mak- 
ing them is so full that the tanner can readily tell the cost. 
Ample allowance is made in the table for waste of material. 
Five-eighths inch round iron weighs one pound to the foot; 
three-fourths inch, one and one-half pound to the foot. 

As the leaches are never quite filled with bark, in figuring 
capacity an allowance of four inches in depth is made. 



LEACHING TAX-BARK, 



213 





Depth 


Lumber, 


|-iuch 


finch 






Capacity per 


Interior 


above 


board 


round 


round 


Number 


Capacity in 


week in 


diameter. 


false 


measure. 


iron. 


iron. 


of days' 


cords. 


cords. 


Feet. 


bottom. 
Feet. 


Feet. 


Feet. 


Feet. 


work. 


Ground bark. 


Ground bark. 


10 


5 


730 


136 




4 


2Hf 


81^8 


10 


6 


798 


136 




4 


Q 6 1 

^T38 


10t¥8 


11 


5 


832 


149 




4 


3f'A 


iOt¥s 


11 


6 


904 


149 




4 


4 26 
^12 "8 


12x^8 


12 


5 


944 


161 




5 


4 16 

^T2"8 


12t*A 


12 


6 


1022 


161 




5 


hh 


l^xk 


13 


5 


1066 


174 




5 


4107 


14t¥^ 


13 


6 


1150 


174 




5 


Hli 


17A\ 


14 


6 


1194 




186 


6 


6x11 


20x¥^ 


14 


7 


1284 




186 


6 


hh 


24tI8 


15 


6 


1328 




249 


6 


1{^ 


^^tA 


15 


7 


1426 




249 


6 


h% 


2VA 
26M 


16 


6 


1458 




268 


6 


8Hf 


16 


7 


1561 




268 


7 


lOI'A 


31f% 


17 


6 


1704 




284 


7 


10t*8 


S^W 


17 


7 


1814 




284 


7 


iHtf 


35V/ 


18 


6 


1772 




300 


8 


iiM 


33l|| 


18 

18 


7 
8 


1888 
2004 




300 
359 


8 
9 


15 3 1_ 

128 


45 93 

138 



As the supply tank is simply a reservoir from which the 
water, or liquor, may be drawn to the leaches in a steady 
stream, the only necessary conditions are that it shall be water- 
tight and placed higher than the leaches. Its form, dimensions, 
distance from the leaches, and relative position, are matters to 
be decided from the plan of the tannery, and by the methods of 
operation in it. 

It is well to have the supply tank as large as it can be con- 
veniently, unless the pump keeps it always filled, and all needed 
heat can be applied at any time, in which case a very small tank 
is sufficient. An " over-flow" near the top will prevent any 
necessity for care lest the pump over-supply the tank. 

A round tank is the cheapest and most durable, but fre- 
quently it is advisable to build in square or oblong form to 
economize space. It is better, of course, to have the reservoir 
near the leaches, if it can well be. 

Steady pressure being desirable — to secure even flow to the 
sprinkler — the reservoir should be quite shallow; three feet 
depth is enough for twelve feet diameter. Any tank in which 
heat is applied should, of course, have a close cover. 

Liquors going to the leaches have to be strained to keep the 



214 



THE MANUFACTURE OF LEATHER. 



boles of the sprinkler from being clogged ; and it is found best 
to strain in the supply tank. Fine brass-wire cloth makes the 
best strainer. 

A loose partition in the tank secures the quiet, unagitated 
flow of the liquor to and through the straining cloth — agitation 
from the pump or steam tending to force bark or sediment 
through the strainer being thus neutralized. 

Fig. 51. 




Fig. 51 shows vertical section of supply-tank, in which both 
direct and exhaust steam are used. All liquors enter from the 
pump-spout a, pass between the boards of the loose partition ?;, 
through the strainer c, and thence through the outlet d. Steam 
entering by the exhaust-pipe e, strikes the plank/, and is diffused 
throughout the tank. The direct steam-pipe is shown at g. A 
plug 7i, may be inserted or withdrawn to close or open the out- 
let f^; a trap-door, ^■, is made in the cover, to allow ready access 
for clearing out, etc. The supply tank should always have a 
loose partition, but no cover is needed unless heat is applied in 
the tank. 

To give head enough to cause the sprinkler to revolve freely 
when the supply in the reservoir is low, the tank should be set 
eighteen inches higher than the top of the leaches. . When a 
pan-heater is used, the tank is to supply the pan ; and that 



LEACHING- TAN-BARK. 215 

should be high enough to give eighteen inches fall. In con- 
nection with an exhaust steam-box, like that shown in Figs. 52 
and 53, the reservoir should be three feet above the leaches. 

"When the pan is used for heating, it should be about eighteen 
inches above the leaches, the supply tank being placed high 
enough to empty into it. The outlet of the pan should be about 
two inches from the bottom, that there may be neither an ex- 
cessive amount of liquor in the pan, nor so little as to expose it 
to burning. In this way a broad thin current of liquor runs 
over the pan from the reservoir to the log leading to the leaches, 
saving heat as much as possible. 

A valve between the supply tank and the pan will regulate 
the movement of the sprinkler perfectly when but ones})rinkler 
is run at a time ; and the valve near the sprinkler should, there- 
fore, be wide open. 

When two or more sprinklers are to be run at once, their 
movement is regulated by the valves near them ; consequently, 
when a valve is used between the supply tank and the pan, 
care has to be taken that the supply is furnished only as fast as 
it can pass to the leaches. A better thing than the valve to 
regulate the flow to the pan is a gate in the tank, the movement 
of which is governed by a float in the pan, for the control is 
perfect, and no oversight is neededj the gate falls (closes) as the 
float rises, and rises (opens) as the float falls, the action being 
similar to that of the beam of a scale ; any carpenter can make 
such an arrangement. 

The steam can be applied either in the reservoir, or in a box 
between the supply tank and the leaches. 

Heating in the supply tank is advantageous when it is desired 
to heat the liquors while leaching is not going on. Heat is thus 
stored up. 

There are many advantages in heating in a box. The steam 
is condensed in a small, steadily changing body of liquid ; con- 
sequently, any degree of heat up to the boiling point can be 
instantly had, and firmly held, without waste or special care. 
Useless dilution of good liquors, if any such are run to the 
leaches, is avoided. Exhaust steam, condensed in a suitable 
box, does not react on the engine ; condensed in the tank, a 



216 



THE MANUFACTURE OF LEATHER. 



column of water is forced out of the exhaust-pipe at each stroke 
of the piston. 

A full description of the making and working of a box suit- 
able for exhaust steam is given below. When steam is the 
only motive power of a tannery, the exhaust will furnish all the 
heat required in leaching ; the exhaust from the engine while 
grinding will usually give heat enough. If the exhaust is not 
sure to give 200° heat to the water or liquor whenever wanted, 
a direct steam pipe should be run to the box to supply any de- 
ficiencies. 

A box suitable for direct steam has a square or round base 
of six or eight inches, and the same height as the supply tank. 
An escape pipe running into the reservoir is advisable. As the 
flow to the leaches is regulated near the sprinkler, the liquor is 
at the same level in the box as in the supply tank. The steam 
pipe should discharge against the bottom of box. 

Fig. 52 gives a perspective view, and Fig. 53 shows a vertical 
section. It is well to have the box about four or four and a 



Fig. 52. 




half feet long, one foot wide and eighteen inches high, inside, 
the outside should be of two-inch plank, and the shelves of one- 
inch pine or hard wood boards, the partition and shelves are 
mortised in. 

Fig. 53 shows correctl}'- the slope and relative position of the 
shelves. They must be placed with care, to make sure that the 
water passing over them shall form a sheet as broad as the box, 



LEACHING TAX-BARK. 



217 



and of equal thickness in all parts. No nails or spikes are used, 
as the steam and metal in contact would burn the wood. 
Wooden yokes, iron bolts, or a combination of both, are used to 
strongly clamp the whole together. 



Fiff. 53. 



^ J 




Water or liquor entering the box, at a, flows over the parti- 
tion, 5, upon the shelf, c, from which it drops to another shelf, 
d, and then to the bottom of the box ; whence it runs through 
the outlet, e, into the conductor leading to the leaches. Exhaust 
steam enters by the pipe,/, and rising into the sheets of liquor 
dropping from the shelves, is instantly condensed. If direct 
steam is also used, it should enter near the exhaust; the waste 
pipe, <7, leads into the tank, or elsewhere, any uncondensed 
steam. Whenever the volume of exhaust steam is found so 
large as to occasionally force back the liquor in the box, — a 
condition of things which rarely happens if the directions are 
followed, — boring a few holes in the lower shelf is the remedy. 

The valve, A, regulates the flow to the box from the supply 
tank, it should also regulate the movement of the sprinkler, 
when but one is run at a time, in which case the valve near or 
over the leach shoald be entirely open. 

When two or more sprinklers are run at one time, as the 
movement of each is controlled by the valve near it, and the 
flow for the aggregate supply is regulated by the valve A, care 
should be taken that the liquor does not back up in the heating 
box and cause irregular action of the sprinkler, unless an over- 
flow to the junk is arranged. This may be done by inserting a 



218 



THE MANUFACTURE OF LEATHER. 



pipe or hollow plug, in the conductor leading from the box to 
the leaches, with outlet of such height that it will overflow^ 
whenever the liquor in the box is more than one or two inches 
deep. 

The outlet e should have two or three times the area of the 
inlet a, as the liquor enters under much greater pressure than 
it leaves. 

The supply of exhaust steam can be regulated easily and per- 
fectly b}^ means of a three-ways cock. Another good method 
for controlling the heat is tempering with water or liquor diredt 
from the tank the hot water or liquor coming from the box ; to 
do this, connect the tank with the conductor at a point beyond 
the steam box, and regulate the supply by a valve. Steam 
should not be run to the box except when wanted to heat. 

A wooden conductor to the leaches is better than metal, for 
it is cheaper, retains heat better, and varies less with changes of 
temperature ; it may be a hollowed log of two and a half or three 
inches bore, or board or plank spout, as most convenient. It is 
well, to save pipe, to place the log or spout about a foot to the 
right or left of the centre of the leach — the metal pipe connect- 
ing the log with the sprinkler should be nearly a foot long; as 
acid soon destroys galvanized iron, brass pipe should be used. 

Fi?. 54. 




Fig. 54 shows a good method of connecting the log and 
sprinkler, and one which permits of but little irregular move- 



LEACHING TAN-BARK. 



219 



ment. Care should be observed in first putting up the fixtures ; 
by placing the rods so that there will be little or no play of the 
elbow, and so that the sprinkler will run on a level, is always 
profitable ; the upper surface of the sprinkler pipe should be just 
below the edge of the leach. 

The flanged elbow h is fastened to a 2 x 6 inch plank c, which 
is supported and braced from above. When the sprinkler is 
first run, assurance should be had that it is well balanced, so 
that the friction shall be as little as possible ; by moving the 
weight in or out, and when in proper place holding it so by 
means of the thumb-screw, this balance is readily and per- 
manently secured ; this is important. 

Fig. 55. 




When it is desired to ran hot and cold, or strong and weak, 
liquors, at the same time, the simplest arrangement of conduc- 
tors is to place them side by side over the centre of the leach, 
fifteen to eighteen inches apart, and have the flow from them to 
the sprinkler regulated by an arrangement like that shown in 
Fig. 55. 



Section III. Filling and Eunning the Leaches. 

It is important to mix the coarse and the fine bark as it goes 
to the leach to prevent unequal action of the leaching fluid, and. 
a little care exhibited in the occasional use of a shovel or scraper- 
is necessary as the leach is being filled, and the tanner should 
also make sure by close examination of the tan when pitched. 



220 THE MANUFACTURE OF LEATHER. 

that the leaoh hand has learned to perform his duty in this 
respect. 

When enough is in the leach to fill it within about four 
inches, the bark should be carefully levelled, and the sprinkler 
should move very near the surface, without exposing it to 
being hurried or delayed by any outside air. 

When the bark goes directly from the mill to the leaches, 
dust in their neighborhood, and the necessity of attention to 
mixing the bark, can be avoided by bringing very small 
streams of hot water or liquor in contact with the bark just 
before it drops into the leach — simply to moisten the dust, and 
cause it to adhere to the larger particles. In a yard in which 
the first run is taken off cold, cold water or liquor may be used 
for this purpose in warm weather. 

Bark should never be floated to the leach, as it parts with 
some of its tannin, and much concentration of liquors, unless 
hurtful doubling is resorted to, is impossible. When there is 
used cold water, or liquor, to float with, much heat is required 
to bring the cold, wet bark to the necessary temperature, and 
this cannot be done without waste of time and the use of a large 
amount of leaching fluid. To float with hot water or liquor is 
even less desirable, as the loss by chemical change is much 
greater. 

The volume of water or liquor run to the leach is regulated 
by a valve, and the movement of the sprinkler is more or less 
rapid as the flow through the valve is increased or diminished ; 
the velocity of the sprinkler may properly be taken as the com- 
parative measure of the quantity of water or liquor given to 
the bark. 

The leaching fluid, distributed steadily and evenly over the 
surface in fine streams, as it presses downward in the leach, 
drop by drop, is gradually absorbed by the bark ; when the 
sprinkler is run slowly, as it should be, it takes nearly two 
hours to wet down the bark so that the liquor will commence 
running through the false bottom. The drops of leaching fluid 
thus pressing down are as numerous as the well-defined parti- 
cles of bark in the leach. As each drop is slowly forced in 
turn, b}'' succeeding drops, the entire depth of the bark, the 



LEACHING TAN-BARK, 221 

bark is rapidly penetrated, and its soluble portions are washed 
out, and in a comparatively small body of liquid. 

Most of the strength of the bark should be taken out while 
running the sprinkler very slowly, for, although a little more 
time is required, the liquors are stronger. When the strong 
liquors needed in the yard have been run off, it is well to run 
the sprinkler more rapidly, to expedite the leaching; for in 
this way the heat of the leaching fluid will more rapily and 
uniformly penetrate the bark. 

The sprinkler should never be run fast enough to cause the 
liquor to collect on the bark ; a moment's reflection will show 
that it will make larger and more irregular channels if it is 
given to the bark faster than it can properly pass down. 

If sediment collects in the sprinkler at any time, upon the 
valve at the end being opened, it will be at once washed out. 

Liquor denser than, water is an inferior leaching fluid ; its 
operation is slower and not so thorough ; bark can be exhausted 
in one-third less time with water only than with old liquors 
chiefly. A leach of hemlock bark, six feet deep, can be ex- 
hausted in twelve or fifteen hours by using water. The usual 
time is from eighteen to twenty-four hours when old liquors 
are employed. 

The leaching should be finished by running through the 
sprinkler water, or a liqaor no heavier, heated to near the boil- 
ing point. For oak bark, raediumly well ground, 180° F. heat 
is enough. For hemlock bark it is well to reach the boiling- 
point, unless it is excellently ground, when 200° F, is enough. 
When such water or liquor has been run through the sprinkler 
for an hour, if the liquor coming from, the leach shows no sign 
of tannin, the bark is leached, and may be cooled for pitching, 
with cold water. 

Water being used as the leaching fluid, a cord of ground 
hemlock bark will give a cord of sweet, pure liquor, weighing 
about 14° by the barkometer, or the equivalent of it ; as the 
barkometer simply shows density, a half cord of liquor weigh- 
ing 28° is the equivalent, or two cords weighing 7°. With 
pure liquors, the barkometer is thus a reliable measure of value. 
In a few cases, owing to peculiar excellence of bark^ a cord of 



222 THE MANUFACTURE OF LEATHER. 

15° liquor is obtained ; and sometimes, although rarely, infe- 
riority of bark will reduce the result to the equivalent of 13° 
liquor. When sufficient heat is used to bring some of the gum 
into the solution, the strength of the resulting liquor is slightly 
increased. Oak bark has usually less strength than hemlock. 
Chestnut-bark will give ordinarily a cord of 11° liquor, or its 
equivalent, for each ground cord. 

If old or weak liquors form the leaching fluid, whatever 
strength they take to the bark is added to the results above 
stated. It should be borne in mind, however, that an old liquor 
possesses less tannin in proportion to its density than a pure, 
new liquor, and that heating and straining it will so sweeten 
and purify it as to perceptibly reduce its strength ; so it does 
not carry to the bark all the strength it apparently has in the 
vat, and when steam is condensed in it there is also some dilu- 
tion. 

The best way to concentrate the strength without doubling, is 
to start with a fair degree of heat and slowly increase it, as the 
leaching progresses, until the boiling point (212° F.) is nearly 
or quite reached. In mild weather 150° of heat is enough to 
have in beginning ; in very cold weather 160° or 170° of heat 
.should be used at the start, to counteract the chill of snow or 
ice on the bark. 

The liquor is cold when it commences to run from the leach, 
but as the leaching goes on it gradually becomes warmer, until, 
just before the bark is exhausted, the temperature of the liquor 
running off is about 30° lower than that of the last, or hottest, 
Avater or liquor run on. The strongest and best liquor is that 
Avhich comes a few minutes after the ooze has begun to run 
from the leach ; from that time the liquor very slowly and 
steadily diminishes in strength, until it is utterly without tan- 
nin, and the bark is spent. It results from this that the 
strongest liquors are obtained with the least heat, and that the 
weak ooze to be run to the next leach, and thus strained and 
cleared in the bark, has in it any gum which may have been 
taken in solution, and a large proportion of the coloring matter 
taken up. It also results that the liquors can be run to make 
any strength desired, and that three-fourths of the strength of 



LEACHIXG TAN-BAEK. 223 

the bark is taken from it in one-half the time required for the 
entire leaching. 

When the leaching is conducted in this way, water, or abso- 
lutely spent liquor, will secure from each cord of hemlock bark, 
in a leach six feet deep above the false bottom, a quarter cord 
of liquor weighing 25° by the barkometer, and a quarter cord 
of each, 16°, 10°, and 5° liquor, about; or, a half cord of 20° 
and a half cord of 8° liquor. The weaker should, as before 
stated, be run to the next leach. The leaching of chestnut-oak 
bark, commenced with 120° to 140° heat, according to weather, 
and increased slowly to 180° to 200°, will give as good concen- 
tration. If liquor possessing some strength is run to the leach, 
the resulting liquors will gain to that extent ; one-half or two- 
thirds of the gain will serve to increase the density of the 
liquors, and the remainder to increase their volume. Deeper 
leaches will secure a little more concentration, and shallower 
ones less. 

Some tanners believe in getting gum into their yard liquors, 
to make sure they get from the bark everything of value in 
making leather. The sprinkler will give them all the gum they 
want, if they will commence leaching with water or liquor 
heated to 200° F. and will keep up the heat. 

The time of leaching, by hot-water methods, ranges from 
twelve to twenty-four hours, according to the density of the 
leaching fluid, the fineness of the bark, and the regularity with 
which the heat is advanced ; but leaches deeper than six feet 
above the false bottom require more time. 

Whenever it is desired to take from bark the larger portion 
of its tannin with the use of little or no heat, the advantages of 
the Allen & Warren system are just as manifest as in the use of 
hot water ; for, without doubling any strong liquors, the. greater 
part of the strength of the bark can be rapidly obtained by 
using, not exceeding, 80° F. of heat — the summer heat of river 
"water — and in as strong solutions as can be had in any other 
way of cold leaching with many doublings. The liquors thus 
obtained by the sprinkler are very clear, have less color, and 
are much purer, having more tannin for the same density. 

Using water at 80° heat, the leach being six feet deep above 



224 THE MANUFACTURE OF LEATHER. 

the false bottom, the first half cord of liquor from each cord of 
ground bark will weigh 13° or 14:°, and its heat will not exceed 
70° ; the later ooze becomes slowly and steadily weaker, unless 
the heat is augmented. By running to the leach partially 
spent yard liquors, or the weaker liquors from the previous 
leach, the greater portion of the strength of the bark can be got 
in liquors ranging from 20° to 16°. When the ooze running 
from the leach is too weak for yard uses, by running hot water 
or spent liquor through the sprinkler the remainder of the 
strength can be rapidly taken out ; the liquors thus obtained 
with heat, when sufficiently cooled, should be used on the next 
leach, where they produce sweet, clear liquors, being cleared 
of all excessive color in passing through the bark. Union 
leather tanners should bear in mind that old liquors are more 
or less sweetened by passing through the bark, even when heat 
is not used, and if they rely upon the liquors alone for acid 
properties in the handlers, they will find them better developed 
in half-spent lay-away liquors than in those fresh from the 
leach. 

The size of the leach or leaches should, of course, depend on 
the amount of bark required to meet the demands of the yard, 
but it is seldom advisable to build a leach less than ten feet in 
diameter, chiefly on account of inconvenience in pitching, or 
larger than sixteen feet in diameter, arising from the consider- 
able bulk ; yet these sizes are as good as any other when adapted 
to the capacity of the yard. 

It is better to have two smaller leaches than one large one, as 
less time is required to fill one* of the small leaches, and less to 
empty it, and their alternate use will supply the liquors required 
more frequently, and, consequently, more nearly as wanted, and 
storage of either fresh or spent liquor is saved. 

When the capacity of two or more large leaches is needed, 
it is better to have them large than to have them smaller and 
more numerous, the difference being economy in tubs and 
fixtures, and simplicity of operation. 

When receivers, or storage vats, are used, it is recommended, 
if practicable, to set the leaches high enough to admit of using 
them without first resorting to a junk aad pump; and the 



LEACHING TAN-BAKK. 225 

receivers maj well be high enough to admit of their contents 
being drawn off to any of the yard vats. 

In the receivers, the fresh liquors needed in the yard are 
always ready for immediate use, and an occasional necessity for 
keeping packs waiting for proper liquors is avoided, and yard 
room is frequently saved, and warm or hot liquors are more 
rapidly cooled. Junk room is reserved for the partially spent 
or weak liquors which are to go to the leaches. 

There should be, in case of such use, a receiver, or a com- 
partment in a receiver, for each grade of fresh liquors required 
in the yard, and to secure the more rapid cooling, as well as to 
avoid placing the leaches very high, the receivers should be 
quite shallow. 

The table of capacity of round leaches previously given does 
not show how many cords of bark, as bought by the tanner, 
they will hold, for a statement of that sort would have to be so 
vague as to be without value. A large number of tanners get 
about sixty heaped bushels, or three-fourths of a cord of ground 
bark for each cord they pay for; few get less than this; few get 
much more ; a few get even cord for cord. 

When compact loads of bark, well taken from the tree and 
flattened by cross piling, are measured by the same rule as light 
loads of unevenly cut and well curled bark, the tanner has to 
find some reliable standard before he can tell how much bark 
he really gets for his money, how much he uses in securing a 
certain result, and whether he is doing better or worse than 
others. There is no more reliable standard, probably, than 
the measure of the bark when ground. The results from a 
certain amount of ground hemlock bark, by the Allen and 
Warren system of leaching, are exceedingly uniform, as the 
foregoing figures show. 

By occasionally comparing the bulk of bark on the wagon or 
sled with its bulk in the leach, the tanner may alwaj^s know 
not only how much he is getting on the average for a cord, but 
how one sort of load compares with another in value. His 
record might well show how many cords of bark, as bought, he 
used during any year ; how many leaches were run, and, con- 
sequently, how many cords of ground bark his purchases 
15 



226 THE MANUFACTUEE OF LEATHER. 

netted ; and the amount and kind of laides worked in, and the 
amount and kind of leather worked out. From this he could 
readily ascertain important facts that not one tanner in a hun- 
dred takes the necessary course to find out. 

Section IV. The Baekometer. 

In the use of the hydrometer, or barkoraeter as it is com- 
monly termed by tanners, it must be kept in mind that it is 
designed simply to determine the density of any fluid thicker 
than water, as compared with pure water. It does not indicate 
of what the fluid consists; the density, or specific gravity, of 
other heavy fluids can be shown just as readily as that of a 
solution of tannin, and be indicated on the stem in the same 
way. The purity, or comparative purity, of a tanning liquor 
being known, the barkometer will show its comparative 
value. 

The barkometer is graded so that when it is placed in water 
at 60° temperature it will stand at 0° ; and the tanning liquors 
to be weighed by it should be at the same temperature, but as 
fluids contract and expand largely as they are cooled or heated, 
if the liquor is warmer than 60°, the barkometer will indicate 
less density than it should ; if colder, greater density. This 
shows the value of a thermometer, to be used in connection 
with a barkometer, as the sense of touch cannot be relied upon 
to indicate the degree of heat. Barkometers made of glass are 
more reliable than any others, for they expand and contract 
less, and although in preparing the liquors it is not uncommon 
also to judge of their strength by the taste, still this is not a 
good guide, and no tanner can afibrd to be without a barko- 
meter. 

It is perhaps necessary also to remark that this instrument is 
applicable only to freshly-made liquors ; for otherwise confusion 
and want of confidence might ensue upon finding that it sinks, 
sometimes, to a corresponding degree in spent liquor, and which 
is owing to the fact that the alterations which tanning liquors 
undergo during use and exposure may not diminish their 
density, though they impair and destroy their tanning power. 



LEACHING TAN-BARK. 227 

Section V. Purifying Extracts of Bark. 

Tan -bark extract, as it comes from the leaches, contains fine 
particles of bark and holds in solution resinous gums. Various 
modes of filtration have been unsuccessful, principally owing to 
the gums in solution choking the filtering material, and the 
gums prevent the deposit of the fine floating particles of bark 
and other foreign substances ; hence a refined fluid extract has 
not heretofore been readily obtainable. Unrefined fluid extract 
of tan-bark ill performs the function of tanning hides, owing to 
the resinous gums and fine particles clogging the pores, and 
prevents or mitigates the penetration of the tannin extract. 
A refined fluid extract in which the gums and floating parti- 
cles of bark, etc., have been removed is a desideratum, and has 
been long sought for. 

The object of the invention shown in Figs. 56 to 62, and 
which is that of Bradley, is to remove by precipitation the 
resinous gums and floating particles of bark from the extract 
emanating from leach-tubs : and the invention consists, first, in 
the process of causing precipitation by concentrating the leached 
extract by artificial evaporation, then rapidly cooling the same, 
and passing the cooled concentrated extract through a series of 
troughs overflowing into one another, wherein the sediment is 
deposited, the pure liquor passing from the surface of the last 
trough into a reservoir at a lower level ; second, in a cooler 
composed of an outer and an inner cylinder, having a tapering 
outlet, and an agitator-shaft, whereby a flow of cold water is 
passed between the cylinders, while the extract to be cooled 
passes through the inner cylinder, which has a central shaft 
with agitating-arms ; third, in combination, a heater or evapo- 
rator, a cooler, and a series of pans arranged to overflow into 
one another for deposit of sediment during precipitation. 

Figure 56 is a side elevation of the apparatus. Fig. 57 is a 
section of the pans, showing levels of extract in passing through 
the same. Fig. 58 is a plan of Fig. 56. Fig. 59 is an enlarged 
sectional view of the cooler. Fig. 60 is a section of Fig. 59 on 
line X X. Fig. 61 is a section on line y y^ Fig. 59. Fig. 62 is an 
elevation of the combined apparatus, showing, in section, a heater 



228 



THE MANUFACTURE OP LEATHER. 



or evaporator (marked M) of any suitable construction, with 
steam -coil N. 






>z 



Fig. 56. 




Fisr. 57. 




Fig. 58. 




The extract, as obtained by leaching the bark in ordinary 
leaches or tubs, is conveyed to an evaporator, and concentrated 
by artificial evaporation to a density of from 7° to 11° of Baume's 
hydrometer, 10° being the preferred density. It is then con- 
veyed while hot to a suitable cooler and rapidly cooled to a 
temperature of from 60° to 80° F. From the cooler the con- 
densed extract passes into a series of tubs of varying heights, 
arranged to overflow into one another, or the tubs may be of 
uniform height, arranged in steps, to receive the overflow from 
one to another and into a long shallow tank, and thence into a 



LEACHING TAN-BAEK. 
Fi":. 59. Fig. 60. 



229 




^-- 




Fis:. 61. 




Fio;. 62. 




230 THE MANUFACTURE OF LEATHER. 

reservoir which receives the purified extract. The sediment is 
deposited in each tub, the grosser particles of foreign matter 
being deposited in the tub nearest the cooler, the finer particles, 
in corresponding ratio, being deposited in the succeeding tubs 
and tanks until the extract, refined from all impurities, flows 
into a storage-reservoir, to be concentrated for market, or into 
the tanning-vats, as may be desired ; or the cooled extract may 
be run off into a series of tubs, as before described, each tub 
provided with a valved outlet, and the extract allowed to stai^^d 
therein until the sediment is precipitated below the outlets, which 
are then opened, whereby the purified extract will flow into 
lower tubs. 

If the extract before cooling is of less density than 9° pr 11° 
Baum^, it will not deposit all the sediment in the tubs, and with 
increased density the deposit will only be partial, and if of the 
density as it comes from the leaches very little precipitation of 
sediment will be effected. 

The lower the temperature of the extract when it comes 
from the cooler, until 60° or 70° F. is reached, the more sedi- 
ment will be deposited in the primary tubs. If the extract is 
filtered before cooling, or if cooled as it comes from the leaches, 
scarcely any sedimentary deposit would be obtained. 

It will thus be observed that the essential elements of this 
process are, first, the rapid cooling of the extract after it has 
been concentrated to a density of from 7° to 12° of Baume's 
hydrometer, to cause the sediment to precipitate ; second, in 
collecting the sediment set free by the cooler in a series of tubs 
and shallow pans, the extract flowing from one tub to another, 
each tub remaining nearly full to let the sediment collect, until 
it finally passes from the trough in an observable clear state. 

Description of Bradley'' s Apparatus. 

The leaches and evaporator need not be further described, as 
they are in ordinary use and well known to all persons skilled 
in the art of obtaining and concentrating extract of barks ; but 
as a suggestion it might be stated that the screw form of evapo- 
rator used by Mr. H. McKenzie, and which is mentioned in the 
list of patients as No. 150,596, on p. 236, could, with but slight 
modifications, be employed in conjunction with this process. 



LEACHING- TA]Sr-BARK. 231 

A B are two concentric cylinders, the outer space forming a 
water-jacket or cooling chamber, of which a is the inlet, con- 
nected to a source of water-supply, and b an outlet to carry off 
the same, thus causing a circulation through the water-space. 

The cylinder B is preferably of sheet-copper, and into the 
space between it and the revolving shaft (7, with agitators d on 
it, concentrated extract, while hot, is admitted through the 
inlet c. 

C is a hollow shaft provided with agitators c?, and which shaft 
is stepped into a bridge e, of the end plate D^ of the cylinder, 
said plate closing the water-space between the two cylinders 
and opening into a conical chamber E^ attached to the bottom 
of plate D^ the outlet provided with a stop- valve/. 

The chamber E has internally a wing (r, a little smaller than 
the conical chamber E^ and is journaled therein by connection 
with the end of the shaft C, to revolve and keep the liquor agi- ' 
tated, and thus prevent the valve / from becoming choked. 
The agitators d are set inclinedly on the shaft in inverse order 
to cause counteraction. 

The agitator-shaft C is driven by connection with a shaft H, 
passing through the end plate of the cylinders A B. 

/are brackets carrying a bearing J, for the shaft H, which 
has a pulley K^ for driving the same by a belt from any suit- 
able motive power. 

The concentrated extract becomes cooled in passing through 
the cooler and falls into a series of troughs or tubs L, arranged 
to flow or to overflow into one another consecutively, the last 
one discharging into a shallow trough L'. The concentrated 
extract, while in these tubs and pan, deposits sediment, the par- 
ticles graduating in fineness from the first tub toward the 
trough L', from whence it passes, by overflow-pipes g^ into a 
suitable receiver, in a clear state, free from sediment. 

Extract which has been concentrated to the ordinary density 
of, say, 30° Baume, without being purified by this process, can 
be purified by diluting it with water to about 10° Baume, and 
while hot passing it through the cooler and thence into the 
troughs to purify the same by precipitation of sedimentary de- 
posit. 



232 the manufacture of leather. 

^Section YI. Obtaining Tannic Acid in Acicular Form. 

The invention shown in Figs. 63 and 64 is that of Holtz, and 
it relates to improvements in the production or manufacture of 
tannic acid for use in the various branches of tire arts and man- 
ufactures, and more particularly in the manufacture of leather. 

The tannic acid employed for technical purposes has been 
heretofore prepared for market by drying the viscous products 
of extraction containing the tannin in a high temperature, aijd 
then grinding the dried product and placing it on the market 
in a pulverulent form. This method of preparing tannic acid 
has material disadvantages and defects, one of which lies in the 
fact that the powdered tannic acid when brought in contact 
with atmospheric air is partially converted into gallic acid, and, 
of course, such a product has not the same value as the pure 
tannin. The presence of gallic acid or other foreign substance 
(the result of oxidation when the tannin extract is dried in too 
high a temperature) becomes at once apparent when the dried 
tannin is dissolved, it being impossible to obtain a clear solution. 
Another defect of this method of preparing tannin lies in the 
fact that the powdered product is exceedingly hygroscopic, 
cakes readily, and is then difficult to dissolve. It dissolves very 
slowly, and even the thoroughly-dry powdered tannin is apt to 
cake or form lumps, which impedes its solution materially. 

The object of Holtz's invention is to remedy these defects 
and produce a practically pure and readily soluble tannin, bet- 
ter adapted for use in the arts and manufactures, and offering 
to the consumer a certain guarantee of its purity ; and to that 
end the invention consists in the production of tannin in an 
acicular form by passing the inspissated tannin extract through 
a finely-perforated sieve, and reeling the thread into bundles, or 
by allowing it to drop from a height into a chamber, at the 
bottom of which it is curled into bundles and then broken up. 
In practice the inventor has found the apparatus illustrated in 
Figs. 63 and 64 best suited, though any other description of ap- 
paratus adopted to effect the same purposes may be employed. 

Fig. 63 is a vertical section of the apparatus, and Fig. 64 a 
bottom-plan view of the reservoir. 

In carrying out this process, take the inspissated viscous 



LEACHING TAN-BAEK. 



233 



solution of tannin (be this a watery or alcohol or other solu- 
tion) obtained in the usual manner, and pour it into a vessel or 



Fiff. 63. 




Fi,?. 64. 




reservoir A, located some distance above the ground, lined with 
copper, zinc, tin, or other suitable material not affected bj the 
tannic acid, and provided with a finely-perforated bottom a, so 
that the mass will pass through said bottom in thread-like form, 
and then reel the threads or otherwise form them in bundles. 
The more economical and easier way, however, is to allow the 
fine streams passing through the bottom of the reservoir A to 
flow from a height into a chamber and cool themselves on the 
bottom thereof in a dried state ; and to that end it is best to 
employ a tower B, about 16 feet and 6 inches in height, with 



234 THE MANUFACTURE OF LEATHER. 

one or more peep-holes /;, and a man-hole ?>', the purposes of 
which are obvious. 

The reservoir A is surrounded by a jacket G, into which an}' 
heat-producing medium (preferably steam) may be introduced 
to maintain the extract in the fluid condition required. 

The bottom c of the jacket has a series of perforations, equal 
in number to the perforations a' in the bottom of the reservoir 
and conaxial therewith, bat of greater diameter. To prevent 
the contact of the steam with the out-flowing extract the per- 
forations are surrounded by small tubes c\ secured to the under 
surface of the bottom of the reservoir and the upper face of the 
jacket-bottom. The use of these tubes c', surrounding the out- 
flow-apertures, produces another and more important result — 
namely, the form-drying chambers, wherein the thread as it 
issues from the reservoir is brought in contact with a heat- 
radiating surface of great area as compared with the surface of 
the outflowing thread-like extract, and which dries this thread 
sufficiently to enable it to support its own weight for a distance 
of five meters before the thread reaches the bottom of the tower, 
being thoroughly dried by the air within the said tower during 
its progress to the bottom thereof, where it curls itself like finely- 
curled wool, and may then be readily broken up into needles. 

It is preferable to make the tower air-tight and produce a 
vacuum therein by any suitable means, such as a force-pump 
connected with a pipe D, located at or near the top of the 
tower, whereby the pressure of the surrounding atmosphere 
upon the viscous tannin extract tends to force the extract 
through the perforations of the bottom of the reservoir, thus 
not only greatly accelerating the operation, but also enabling a 
more concentrated solution to be employed than would be the 
case if the passage of the latter depended solely on its weight. 

The tannin threads when cold are exceedingly brittle, and 
break into shining golden-yellow acicular fragments, and in 
this acicular form the tannin, owing to its brittle or glass-like 
condition, is not hygroscopic, will not cake, and a perfectly 
clear solution is obtained therefrom. 

The tannin being prepared under the influence of a low tem- 
perature does not contain any products resulting from decom- 
position, such as above enumerated. 



LEACHING TAN-BARK, 



235 



List of all Patents for Processes and Apparatuses for Leaching and 
making Extracts from Tan-hark, issued by the Government of the 
United States of America, from 1790 to 1883 inclusive. 



No. 


Date 


1. 


Inveutor. 


Residence. 




Aug. 10, 


1791. 


J. Biddis and 




• 






S. T. Bedwell, 






Oct. 20, 


1812. 


J. W. Fessenden, 


Walpole, N. H. 




April 5, 


1823. 


W. Knapp, 


Milford, N. Y. 




April 11, 


1825. 


J. Niles, 


Guilford, Vt. 




Mar. 15, 


1825. 


W. Leber, 


Philadelphia, Pa. 




Nov. 1, 


1828. 


W. Coburn, 


Gardiner, Me. 




Nov. 7, 


1835. 


0. Batchelder, 


Bedford, N. H. 


836 


July 12, 


1838. 


A. A. Hayes, 


Roxbury, Mass. 


1,035 


Dec. 15, 


1838. 


G. W. Klein, 


Boston, Mass. 


13,403 


Aug. 1. 


, 1855, 


G. W. Smith, 


Nanticoke, N. Y. 


14,418 


Mar. 11, 


, 1856. 


A. Steers, 


Medina, N. Y, 


Reissue 










2,142 


Jan. 2, 


1866. 


A. Steers, 


Medina, N. Y. 


27,859 


AprillO, 


1860. 


J. Connell, 


Port Huron, Mich. 


29,143 


July 17, 


1860, 


J. Connell, 


Port Huron, Mich. 


34,873 


April 8, 


1862, 


J. Brainerd and 


Cleveland, 0, 


Reissue 






W. H. Burridge, 




2,523 


Mar. 19, 


1867. 


J, Brainerd and 
W. H, Burridge, 


Cleveland, 0, 


36,048 


July 29, 


1862. 


Wm. H. Allen and 


Freyburgh, Me. 


Reissue 


Jau. 3, 


1865, 


0. Warren, 




1844 










41,782 


Mar. 1, 


1864, 


S. W. Pingree, 


Lawrence, Mass, 


47,393 


April 25, 


1865. 


J. Chilcott, 


Brooklyn, N. Y, 


45,421 


Dec. 13, 


1864, 


J. McGeary, 


Salem, Mass, 


48,365 


June 27, 


1865. 


J. M. Caller, 


Salem, Mass, 


50,636 


Oct. 24, 


1865. 


S. W. Pingree, 


Lawrence, Mass. 


54,945 


May 22, 


1866. 


F. W. Perry and 
J. H. Pierce, 


Woburn, Mass. 


57,218 


Aug. 14, 


1866. 


N. S. Thomas, 


Painted Post, N, Y. 


64,321 


Apr. 30, 


1867. 


B. Irving, 


New York, N, Y. 


64,322 


Apr. 30, 


1867. 


B. Irving, 


New York, N. Y, 


64,323 


April 30, 


1867. 


B. Irving, 


New York, N. Y. 


64,324 


April 30, 


1867. 


B. Irving, 


New York, N. Y, 


64,325 


April 30, 


1867, 


B. Irving, 


New York, N. Y, 


68,010 


Aug. 20, 


1867, 


A. Steers, 


New York, N. Y, 


68,335 


Sept. 3, 


1867. 


A. Appleby, 


Brownfield, Me. 


70,439 


Nov. 5, 


1867. 


J. W. Jones, 


Cumberland, Md. 


71,765 


Dec. 3, 


1867. 


C, Korn, 


Wurtsborough, N, 1 


75,571 


Mar. 17, 


1868. 


S. J. Patterson, 


Bridgeport, Conn. 


75,608 


Mar. 17, 


1868. 


G. Warren, 


Roxbury, Mass. 


76,775 


Apr. 14, 


1868, 


J. W. Jones, 


Cumberland, Md. 


81,643 


Sept. 1, 


1868. 


T. W. Johnson, 


New York, N. Y. 



236 



THE MANUFACTUEE OF LEATHER. 



No. 


Date. 


Inventor. 


Residence. 


82,121 


Sept. 15, 


1868. 


T. W. Johnson, 


New York, N. Y. 


82,739 


Oct. 6, 


1868. 


C. H. Mosely, 


Winchester, Mass. 


83,389 


Oct. 27, 


1868. 


T. W. Johnson, 


New York, N. Y. 


85,173 


Dec. 22, 


1868. 


B. Irving, 


New York, N. Y. 


85,174 


Dec. 22 


1868. 


B. Irving, 


New York, N. Y. 


85,175 


Dec. 22, 


1868. 


B. Irving, 


New York, N. Y. 


87,119 


Feb. 23, 


1869. 


S. Snyder, 


Cincinnati, 0. 


87,984 


Mar. 16, 


1869. 


Gr. A. Starkweather, 


Waymart, Pa. 


88,678 


Apr. 6, 


1869. 


N. S. Thomas, 


Painted Post, N. Y. 


88,807 


Apr. 13, 


1869; 


J. Pickles, 


Wigan, England. 


90,848 


,Iune 1, 


1869. 


T. W. Johnson, 


New York, N. Y. 


92,455 


July 13, 


1869. 


T. W. Johnson, 


New York, N. Y. 


95,009 


Sept. 21, 


1869. 


L. C. England, 


Philadelphia, Pa. 


96,212 


Oct. 26, 


1869. 


L. C. England, 


Philadelphia, Pa. 


96,345 


Nov. 2, 


1869. 


J. Pickles, 


Wigan, England. 


102,832 


May 10, 


1870. 


S. W. Kennedy, 


New York, N. Y. 


108,793 


Nov. 1, 


1870. 


T. W. Johnson and 


New York, N. Y. 


Reissue 






A. W. Goodell, 




4.531 


Aug. 29, 


1871. 


T. W. Johnson and 
A. W. Goodell, 


New York, N. Y. 


111,730 


Feb. 14, 


1871. 


H. C. Crovrell, 


Morgan, 0. 


118,956 


Sept. 12, 


1871. 


W. Maynai-d, 


Salem, Mass. 


134,675 


Jan. 7, 


1873. 


T. W. Johnson and 
A. W. Goodell, 


New York, N. Y. 


137,004 


Mar. 18, 


1873. 


C. Korn, 


Brooklyn, N. Y. 


140,469 


July 1, 


1873. 


P. M. (Jhurch, 


Sault de Ste. Marie, Mich 


150,595 


May 5, 


1874. 


H. McKenzie, 


Marquette, Mich. 


150,596 


May 5, 


1874. 


H. McKenzie, 


Marquette, Mich. 


150,597 


May 5, 


1874. 


H. McKenzie, 


Marquette, Mich. 


187,468 


Feb- 20, 


1877. 


T. W. Johnson, 


New York, N. Y. 


193,120 


July 17, 


1877. 


J. J. Johnson, 


Columbiana, 0. 


218,212 


Aug. 5, 


1879. 


R. R. Andrews, 


Smithport, Pa. 


230,.398 


July 27, 


1880. 


E. Bradley, 


Three Rivers, Quebec, 


231,035 


Aug. 10, 


1880. 


P. Gondolo, 


Paris, France. [Can 


231,489 


Aug. 24, 


1880. 


Julius Holtz, 


Berlin, Prussia. 


245,006 


Aug. 2, 


1881. 


G. B. Moore, Sr., 


Cincinnati, 0. 


245,142 


Aug. 2, 


1881. 


J. Davis, 


Allegheny, Pa. 


253,802- 


Feb. 19, 


1882. 


M. Wise, 


New York, N. Y. 


258,573 


May 30, 


1882. 


P. Gondolo, 


Paris, France. 


258,574 


May 30, 


1882. 


P. Gondolo, 


Paris, France. 


259,555 


June 13, 


1882. 


0. Kolrausch, 


Vienna, Austria-Hung. 


263,797 


Sept. 5, 


18h2. 


A. Mitscherlich, 


Munden, Germany. 


283,881 


Aug. 28, 


1883. 


P. Gondola, 


Paris, France. 



Note. — For portions of the matter relating to building round leaches and 
filling and running the sprinkler leach, contained in this cliapter, the author 
desires to acknowledge the source of his information, which has been derived 
from a valuable catalogue published by Messrs. Allen & Warren, now of Con- 
way, N. H. 



PART ly. 



CHAPTER XIII. 

WASHING AND SOAKING HIDES AND SKINS — PROCESSES FOR SOFT- 
ENING HIDES, SKINS, AND PELTRIES — LIST OF AMERICAN 
PATENTS FOR COMPOUNDS FOR SOFTENING HIDES — PROCESS 
FOR PLUMPING BEFORE DEPILATING. 

Section I. Washing and Soaking. 

In the manufacture of leather the hides and skins destined to 
be tanned or tawed and converted into this product are sub- 
jected to various preliminary operations, the nature, variety, and 
duration of which depend upon the condition of the hides or 
skins when they arrive at the tannery, and also upon the class 
of leather that it is desired to produce. The "green" hides are 
those from recentlj^ slaughtered animals, and are soaked for a 
short time in water so as to remove the blood and adhering 
dirt, and are to be well raised when taken from the soaking, 
and if to be soaked for a long period, it is necessary to handle 
them from time to time. 

The dry hides are soaked for a longer period than the green 
hides, and afterwards they are worked in the hide-mill, and so 
through the whole class of hides, there are different processes 
to which they must be subjected. In order to achieve satis- 
factory results in every step of the production of leather, it is 
imperative that there should be similarity of state which must 
be such as will be conducive to success. Foremost among 
these demands, there must be a sameness in the condition of 
the hides at the beginning. 

The proper selection of hides, according to variety, size, thick- 



238 THE MANUFACTURE OF LEATHER. 

ness, and condition, is of course a difficult problem, but as these 
matters are to decide the final value of the finished leather, it is 
absolutely essential that the most intelligent judgment be exer- 
cised at this. point, for if there be not proper consideration here 
there will be loss throughout all the subsequent processes, conse- 
quently a final diminution of profit. All'tanners are, of course, 
not so situated as to make it expedient to so assort the hides ; 
but where it is possible, the classification should be made, and 
the hides of the greatest substance should be picked out and 
first worked in, thereby allowing a simultaneous completion at 
each step of the process, by which arrangement it would be much 
easier to detect and rectify mistakes. 

It is well known that during the continued submersion of 
hides in vats of water the variations in the temperature of the 
weather and of the water and in the quality and purity of the 
latter, which is constantly being rendered unfit for its designed 
purpose by the continued accumulation of decomposed particles 
of flesh and fibre from the hides, there is more or less damage 
and injury to the hides, which suffer a loss of gelatine and fibre 
and appear spotted in what are known as " black rot," black or 
yellow spots, and damage in the process of sweating or liming, 
usually called " pricks," " pitted," and " frieze." It follows 
that if these natural results of the necessary steps of procedure 
in tanning are overcome the product will not only have a 
clearer superficial appearance, but its texture and fibre will be 
more uniformly of natural thickness and of desired firmness 
than is now the case. 

In the usual first step in the art of tanning — that is, soaking 
the hides in clean water — pricks, pitted, frieze, and black spots 
originate. The hide decomposes before it is properly softened, 
which decomposition is sufficient to cause the above-named in- 
juries, and no subsequent use of saltpetre or any other restora- 
tive can prevent them. 

The term "prick" indicates an appearance such as would be 
produced by puncturing the hide with pins, and this injury is 
produced by soaking for too long a time, especially in hot 
weather, and it may also be produced in a subsequent step in 
the art known as "sweating." "Pitted" indicates an appearance 



WASHING AND LEACHING. 239 

much similar to the above, but the holes are much larger. 
" Frieze" is principally caused in the subsequent step of sweat- 
ing when the grain of the hide is inclined to be tender and has 
the appearance of being scraped off. " Black spots" are small 
blotches of dark color, and when the hide is tanned, rolled hard, 
and finished, these spots cannot be buffed off', and sometimes 
cover the whole side of leather. They originate in soaking 
and sweating. As these injuries originate directly or indirectly 
in the soaking of the hides at the commencement of the process 
of tanning, the use of a preventive at that time is of great im- 
portance. Hence Mr. John W. Hammond, of Osceola, N. Y., 
who claims to have invented the following process of soaking, 
uses saltpetre in the first step in the procedure. 

By subjecting hides, either dry or green, to the action of 
water containing a proper proportion of saltpetre or nitrate of 
potassa for a proper length of time and at a proper temperature, 
he claims that they are the better prepared to withstand the 
deleterious effects of the usual subsequent liming and sweating; 
processes and of the process of plumping and coloring in the; 
handlers. 

The principle upon which this manner of soaking is based is 
that before subjecting the hides to the decomposing and destriaic- 
tive action of the sweating and liming processes, in order toi 
swell and soften the fibre, to the end that the hair may be re- 
moved and the pores opened for the entrance of the tanining 
agents, this swelling and softening should be accomplished 
through the medium of an agency which will at the same time 
act to preserve the life and fibre of the hide, instead of hasten- 
ing its W3,ste and decomposition. 

The use of saltpetre in tanning is not new, it having been 
already used as an ingredient in tanning liquor, but experience 
has shown that desirable results are not secured in so great 
measure by such use as when its effects are given solely and 
primarily and under the conditions hereafter stated. 

In practice the use of this preparatory treatment depends 
upon circumstances, as to quantity, temperature, and time, that 
are within the discretion of the skilled tanner, and this from the 
variableness of the condition and quality of the hides to be 



240 . THE MANUFACTURE OF LEATHER. 

treated, the temperature of the atmosphere, and the state of the 
weather ; but as a basis or rule of general application the follow- 
ing-mentioned proportions and particulars it is claimed are 
practical and beneficial in result, though changes may be made 
in them by reason of the before- mentioned conditional circum- 
stances, so that the exact proportions, temperature, and time 
are not vital essentials. For twenty-five hundred pounds of 
dry hides and the same proportion of green hides use sufficient 
water to cover or hold that quantity of hides, and intermix 
with the water before putting them into it from one to six 
pounds of saltpetre, the same being dissolved in warm water 
and then added to the water in the vat, the hides being sub- 
jected to immersion therein, with more or less frequent handling 
in order uniformly to expose each hide to the full effects of the 
liquor for from two to thirty days, and at a medium tempera- 
ture. It will be seen that the temperature of the liquor should 
be comparatively higher in cold and lower in warm weather, 
the proportion of saltpetre increased with the increased propor- 
tion or quantity of hides, as also the time of treatment, all of 
which is a matter of judgment iu the province of one skilled in 
the usual methods of tanning. 

Hides so treated it is claimed assume a plumpness and firm- 
ness, the pores are opened, and the hair-cells are softened and 
distended, rendering the subsequent liming and sweating pro- 
cesses shorter and more effective and the subsequent tanning by 
submersion less destructive to substance and fibre, and reducing 
liability to spot. Hides so treated it is claimed can be worked 
in the processes of soaking and sweating with much higher 
temperature of weather and water than by the ordinary well- 
known processes. 

All grease should be removed from the hides during the 
soaking, or they will not sweat properly, and if grease is still 
present after the usual method of soaking and milling, then the 
use of soda-ash, potash, sal-soda, or an equivalent alkali is re- 
commended, and in lieu of these hard wood ashes may be used 
in the soaks if more convenient, as these agents convert grease 
into a soap, which will wash from the hide very easily in the 
mill. 



WASHING AND SOAKING. 241 

Small hides or kips, after being well washed and cleaned, are 
sometimes soaked bj laying them in foul bloody water. This 
method, which is in use amongst white tanners, requires much 
attention, like every other process by means of which the hide 
is restored almost to its original condition. 

It imparts a perfect softness to the hide, leads rapidly to the 
result, and is not costly ; but it requires the greatest precau- 
tions. 

Another method is the softening of the hide by " sweating," 
that is to say, heating it without fire and without steam, and of 
the sweating process, as generally employed, we shall treat in 
Chapter XY. " 

With regard to imported salted hides, a proper softening in 
water will do, and this water should be changed every now 
and then, so that the hides do not remain long in briny water, 
and care should be taken to rinse them thoroughly before plac- 
ing them in the fresh water. 

Of the influence of water upon the quality of the leather we 
have spoken in Chapter IX. Of the period which the hides and 
skins are allowed to remain in the soaks and their usual treat- 
ment for different classes of leather we shall enlarge upon in 
the descriptions of the methods of manufacturing sole leather, 
upper leather, Morocco leather, etc. It is not of course intended 
that the processes to which reference has just been made should 
be considered as dogmatic, for no two tanners treat hides in the 
soaks, sweating, liming, or other steps in tanning, in exactly the 
same manner and for the same period ; some tanners advocate 
light soaking, while according to others the quality of the leather 
is improved in proportion to the duration of the soaking of the 
hides; but it is undeniable that when it exceeds a certain time 
the skin acquires a tendency to decomposition, and the quality 
of the leather is impaired. 

The construction and operation of the hide-mill is explained 
in Chapter XIY., and is usually employed after the soaking of 
dry imported hides. 

When the hides are dry the soaking should be continued 
longer, and that operation is facilitated by handling them often. 
The hides are to remain in water until they have become supple, 

16 



242 THE MANUFACTURE OF LEATHER. 

and it is for the intelligence of the workman to determine when 
this point is attained. Dried and salted hides require a much 
longer soaking than those which have only been dried. 

The working and softening of the dry hides in the hide-mill, 
or upon the horse or beam, are considered indispensable opera- 
tions by every experienced tanner, in order to remove the stiff- 
ness and wrinkles, and are of course unnecessary for green hides. 

When the hides have all been soaked and washed, and are 
sufficiently supple, after being worked in the hide-mill, they are 
returned and left in the water for six hours. In running water 
they may remain eight hours. Reference is here made exclu- 
sively to large hides, for cow skins may be left without danger 
for 24 hours, and calf skins 48 hours, being careful to observe 
the nature of the water and the temperature of the air. Too 
long soaking in the same water exposes the skins to the danger 
of putrefaction, and the rapidity of the decomposition is propor- 
tional to the amount of filthy matters contained in the water. 

In some parts of France, hides from South America are 
placed directly in vats filled with lime-water and left for six to 
ten days, care being taken to work them in the usual manner at 
frequent intervals during the soaking. The skins are softened 
by the action of lime and rendered more easy to be handled. 
At this stage the defective parts may be detected, and some- 
times they are so damaged as to be suitable only to manufacture 
glue. 

Well-salted hides, but not dried, may be cleansed in 48 hours, 
but they can be left to soak three or four days without danger. 
They should be handled once a day. When taken out from the 
water for the last time they should be given a vigorous and 
thorough rinsing. 

It is the usual custom in the manufacture of upper leather, 
after hides have been properly soaked, to split them into " sides ;" 
previous to which operation they are drawn into a pack with 
the hair side uppermost, and then a knife is driven from the 
butt through the centre of the backs, which divides the hides. 



SOFTENING HIDES. 243 

Soaking Dry Hides in Banning Water. 

As there is still a large amount of soaking of dry hides done 
in running water, we give separate directions for conducting it. 

The water should have a temperature not above 55° F. 
According to the prevailing arrangement, the dry hides are 
suspended by chains or ropes, or hung over a pole. After 
twenty-four hours they will be sufficiently soaked to be rinsed, 
after which they are bent apart and replaced in the water. 

They are now rinsed every twelve hours, partly for the 
purpose of changing the position of the hides so that the 
soaking will be uniform, and partly to prevent mud and other 
impurities from settling upon them. After six days they 
are generally sufficiently soaked to allow them to be subjected 
to the sweating process ; more than eight days' soaking being 
required only in rare cases ; but this is of course dependent 
upon the nature and condition of the hides. 

After the hides have been soaked and swelled so that they 
can be readily bent (especially the head), and the escutcheon 
has assumed a glassy appearance, they are removed from the 
water, it heing of the utmost imi:)OTta,nce that in doing this, they 
are cleansed from all dirt and impurities. It is best to use for 
the latter purpose a worn-down broom, with which they, and 
especially the hair sides, are scrubbed until all dirt is removed 
and the rinsing water runs off clear. 

After folding them in the middle and tucking in both ends, 
they are piled one upon the other until all are cleansed. 

They are then thrown over a bench and allowed to drain off 
for a few hours, or over night. 

Section II. Processes for Softening Hides, Skins, and 

Peltries. 

Softening Dry Hides^ Skins, and Peltries, hy Soaking them in 
the Waste Water from Gas Works. 

It is known to tanners that serious inconvenience exists in 
the processes used for the purpose of softening dry hides. The 
one commonly employed consists in immersing them in a bath 



244 THE MANUFACTURE OF LEATHER. 

of water, together with various subsidiary aids, such as scraping, 
beating, working them in the hide-mill, etc. 

The serious inconvenience experienced in this mode is the 
well-known liability of the hides to putrefy before they are 
sufiiciently softened to be ready for the lime process. 

Another objection to the use of the common method is that 
in cold weather the length of time required for softening is so 
great as to be a serious loss to tanners. Then, again, there is a 
risk of destroying the hides if softened during very warm 
weather. 

It is claimed that by the use of waste gas- water the above 
objections can be obviated. 

Barron's Process. 

The agents which this inventor claims to be the most eft'ectual 
for softening dry hides, skins, and peltries are : The reluse 
liquid of gas-works in the refining process ; gasoline ; and coal- 
tar. The refuse liquid is employed either alone or slightly 
diluted with water. When gasoline is used it is diluted with 
water in about the proportion of one part gasoline to twenty 
parts water. But exactly the best proportion cannot be defi- 
nitely stated, inasmuch as the strength of the soak will vary 
according to circumstances, such as the character of the hides 
and the state of the weather, etc. The above proportions, it is 
stated, will generally answer, but may with safety be somewhat 
varied by slightly less diluting in winter and more in summer. 
The coal-tar, however, will not answer when taken alone, nor 
is it' sufficiently soluble in water to be made available with . 
water only. To be used effectively it must, by the aid of an 
alkali, be dissolved in water. Caustic soda will answer as the 
alkali for the above purpose ; and the following proportions, it 
is claimed, will give beneficial results — to wit : five gallons coal- 
tar, three pounds caustic soda, and one hundred gallons of 
water. 

Each of the above mixtures, it is claimed, contains substan- 
tially similar active agents, viz : water, alkaline matter, and 
antiseptics. The alkalies of the above are mainly ammoniacal 



SOFTENING HIDES, 



245 



salts in solution. The antiseptics consist principally of soda 
carbolate and cresylate. 

The action is as follows : The water is the principal soften- 
ing agent ; the alkalies remove the fatty parts of the hide, 
and have a peculiar softening effect upon the hide, and, when 
taken in connection with the action of the antiseptics, it is 
claimed, have no injurious effect upon its tissue. The anti- 
septics preserve the hides from putrefaction while undergoing 
the above process, and it is claimed that by being to some ex- 
tent incorporated into the tissue of the hides preserve them 
from putrefaction for a greater length of time after they have 
been softened — in case the hides do not go immediately into the 
lime — than any process heretofore known. 

When the liquor has been mixed in the vat, as above described, 
the hides are immersed therein, and receive substantially the 
same treatment, as regards stirring, mixing, etc., that they 
would receive under the old processes, and remain therein until 
they are sufficiently softened. The time required for softening 
will vary in the same manner, though not to so great an extent 
as in the old processes, and will, the year round, require on an 
average, it is claimed, not more than one-half of the time re- 
quired by the process now in general use. 

Berry'' s Process for Softening Hides. 

This process was patented by Berry, and is for softening 
dry hides intended for sole or upper leather, the ingredients 
being: : — 



Slaked lime 


. J bu. 


"Wood ashes 


. |bu. 


Potash (dissolved in water) 


. 12 lbs. 


Oil of vitriol , . . ... 


5 lbs. 


Spirits of salts 


. 4 lbs. 



These substances are placed in a vat of water capable of hold- 
ing twenty-five dry sole leather hides, and after being well 
stirred the hides are placed in it and remain three or four 
days. They are next placed in a preparation for unhairing, 
composed of — 



246 THE MANUFACTURE OF LEATHER. 

Slaked lime ...•..! bu. 
Wood ashes ...... 1 bu. 

Potash (dissolved in water) . . . 4 lbs. 

From the last liquor they are drawn every other day until 
"raised," and when the hair begins to start they are split into 
sides and placed in " lime liquor," and handled every day until 
they are fit to "unhair," and from this point the treatment is- 
as usual. 

List of all Patents for Softeniny^ Hides, issued hy the Government of 
the United States of America, from 1790 to 1883 inclusive. 



No. 


Date 




Inventor. 


Residence. i 




Feb. 4, 


1833. 


A. McMillen, 


Bedford, N. H. 




Mar. 6, 


1833. 


Wm. Berry, 


New Sharon, Me. 


127,947 


June 18, 


1872. 


J. Barron, 


Chicinnati, 0. 


152,908 


July 14, 


1874. 


J. D. Marshall, 


Chicago, 111. 


234,248 


Nov. 9, 


1880. 


Wm. Coupe, 


South Attleborough, Mass, 



Section III. Process for Plumping before Depilating, and 
THE Treatment of Hides or Skins with an Acid Solution 
BEFORE Liming, for the Eemoval of Salt or other Mat- 
ters. 

Mr. Homer Ely, of Balston Spa, New York, has invented a 
process for " plumping" hides previous to depilating, and it 
consists in a method of softening and preparing the hides and 
skins as a preliminary to the action of the tannin liquor, and, 
though applicable to skins in either the fresh or salted state, 
it is claimed to be particiilarly applicable to hides and skins 
which have been previously salted. 

In carrying out the process, place the hides or skins in a 
vat of clear water, allowing them to remain a sufficient time to 
soften and remove all the dirt or other foreign substances that 
may adhere to the surface, and also to soften the hitherto dry 
and hard hides or skins sufficientl}^ to allow them to be divided 
down the back into halves, technically called " sides," The 

' In addition see patents Nos. 59, 627, 136,081, and 226,447, described under 
the head of Depilating. See, also, list of Patents for Hide-Mills and Boarding 
Machines. 



PLUMPING BEFORE DEPILi.TING. 247 

hides remain in this first vat for twenty-four hours, when they 
are sufficiently softened to be taken out and divided. When 
the dividing is performed, place the sides in a vat, preferably 
suspending them by hanging them over bars in a vertical posi- 
tion, twenty sides being a convenient number to operate with 
in a single vat. For this number of sides the inventor uses in 
the vat a solution of sulphuric acid in water, in the proportion 
'of five pounds of commercial sulphuric acid in about twenty-one 
hundred gallons of water, which will cover the above-specified 
number of sides when properly placed in the vat. The action 
of this solution is to decompose all the salt remaining in the 
hides or skins. It also softens the gelatine, and opens the pores 
of the hides or skins, exerting that action upon them which is 
technically known as "plumping," The pores of the surface 
of the skin are opened in this way for the easy and rapid 
escape of any deleterious matter contained therein. 

During the process of plumping, all earthy impurities pre- 
viously adherent to the hide are thrown out of the pores of the 
skin, and deposited at the bottom of the vat in the form of a 
dark-colored-sediment, which is easily washed out of the vat by 
the aid of clear water. The hides are in this way, it is claimed, 
thoroughly soaked, plumped, and cleansed, and, at the same 
time, such portions of flesh as still remain adhering to the hide 
are softened, so that they are very easily removed. 

In order to complete this second step in the process thor- 
oughly, the hides or skins are subjected to the action of the 
sulphuric acid solution for from eighteen to twenty hours. 
The acid solution is then drawn off from the vat, and the hides 
or skins are rinsed thoroughly with clear water. Then remove 
the hides or skins, and place them in another vat containing 
about fifteen hundred gallons of water. Then dissolve in a 
sufficient quantity of water, to make the solution perfect, two 
pounds of sal-soda and five quarts of soft soap. After these 
materials are thoroughly dissolved, add the sal-soda and soap 
solution to the contents of the last-mentioned vat. The action 
of the soap upon the hides or skins is to neutralize the remain- 
ing acid in the pores thereof, a certain quantity of the soap be- 
ing decomposed, and its alkali uniting with the acid to form a 



248 THE MANUFACTURE OF LEATHER. 

soluble salt, which is soaked oat in the water of the vat. A 
certain amount of oleine, margarine, or stearine, contained in 
the soap, remains in the texture of the hides or skins, together 
with a little glycerine. The action of the sal-soda is to keep 
the hides plump and pliable. When it is omitted from the 
solution they become shrunken and flat. It is best always to 
obiserve the precautions to have a slight excess of the soap and 
sal-soda over and above the amount necessary to neutralize the 
remaining acid in the hides or skins, and to allow the hides or 
skins to remain in the vat containing the soap and sal-soua 
solution for twenty-four hours, at the end of which time they 
are ready for liming. 

In the liming the inventor prefers to adhere to the ordinary 
course employed by tanners, using nothing but lime. After the 
hides have passed through the lime, and the hair is removed, 
work them out of' soft warm water, and then the inventor fol- 
lows the usual course through the " bating." He allows them 
to remain in the bate three days, after which they are thor- 
oughly milled, and then, in as rapid succession as possible, they 
are three times handled in or passed through a solution com- 
posed of about twelve hundred gallons of water and three 
pounds of sulphuric acid, the solution being maintained at a 
temperature of about 100° F. This treatment neutralizes any 
lime there may be remaining in the hide, and also removes the 
roughness that sometimes shows itself on the hair side of the 
hides or skins when the bate is not in a proper condition. If 
the hides or skins have not been sufficiently softened in the 
bating, all the remaining hardness will be removed, it is claimed, 
by the action of the last-mentioned solution. From this solu- 
tion the hides or skins are passed into another vat containing 
about twelve hundred gallons of water to which two pounds 
of sal -soda and five quarts of soft soap, previously dissolved 
in soft water, are added. The hides are handled in or 
passed through this solution twice, and are allowed to re- 
main two hours in the solution after handling. They are 
now ready for the final working or beaming previous to 
their treatment with the tanning liquor. After they have been 
thoroughly worked or beamed, they are thrown into a vat of 



PLUMPING BEFOKE DEPILATING. 24:9 

water maintained at a temperature of from 90° to 100° F., in 
wbich has been previously dissolved saltpetre, in tlie propor- 
tion of one ounce to about thirty gallons of water. In this vat 
they are allowed to remain for one hour. The action of the 
saltpetre on the hides or skins, it is claimed, is to " plump" or 
" raise" them, as it is called, facilitating the swelling of the 
gelatine in the tissue of the skin, and preparing the way for the 
free admission of the tannin. 

The hides or skins are then ready for the action of the bark 
or tanning solution in which they are then placed. After hav- 
ing reached this stage in the process of converting skins into 
leather, the inventor follows in every particular the original 
process of tanning, by the use of barks containing tannic acid, 
using nothing but bark in the water of the vat, and discarding 
everything else of a chemical nature. By this process the in- 
ventor claims to be enabled to dispense with the operation 
known to tanners as " fleshing," and also to save at least one- 
fourth of the time employed in converting skins into leather 
by the usual method. By this process the inventor claims to 
also utilize for glue manufacturing or other purposes a large 
quantity of fleshy substance, which is usually thrown away, 
and also to decrease the expense of time and labor, and facilitate 
the process of handling, which is performed in a more satisfac- 
tory manner. 

The advantage claimed to be obtained by plumping before 
liming is, that it opens the pores of the surface of the skin, so 
that the dirt and other deleterious matter which would other- 
wise obstruct subsequent processes escape freely, and settle to 
the bottom of the vat. 

By this process the inventor claims also to obtain an improved 
quality in the leather, and that the hide acquires a greater degree 
of softness, pliability, toughness, strength, and weight than by 
any other process. These qualities, it is claimed, are obtained by 
preparing the hides so thoroughly for the reception of the tannin 
as to obviate the necessity of using other chemicals with the 
tannin, and yet to admit of the hides or skins being tanned 
perfectlyin a short space of time. 

By supplementing the bating by the action of sulphuric acid, 



250 THE MANUFACTURE OF LEATHER. 

the inventor claims to avoid any weakening or other injury of 
the leather by putrefactive action in the bate, which sometimes 
occurs when the bating is too long continued. 

Although we have specified the proportions of acid and 
water in the above-named solution, and the proportions of sal- 
soda and soap to be used for a given amount of water, it is 
claimed that it is not necessary to be strictly confined to these 
proportions, but that the strength of all the solutions may be 
varied according to the condition of the hides or skins. 



CHAPTEE XIV. 

HIDE- MILLS — LIST OF AMERICAN PATENTS FOR HIDE-MILLS — LIST 
OF AMERICAN PATENTS FOR BREAKING HIDES. 

It is usual to soften dry hides and skins in the hide-mill 
after they come from the soaks and have been divided into 
"sides," and previous to subjecting them to the liming process, 
and the time which they are worked in this mill depends upon 
the hardness or softness of the hides or skins. For the sides that 
are intended to be worked for upper leather, the usual time is 
from one-quarter to three-quarters of an hour, while skins that 
are intended for the production of Morocco leather are usuall}^ 
worked from ten to twenty minutes. 

The construction of hide- mills differs greatly for the various 
branches of leather manufacture. Those employed for softening 
hides and kips are similar to the fulling mills common in 
woolen factories ; while the mills used for manipulating skins, 
such as goat and sheep skins intended for the production of 
Morocco leathers, are sometimes in the form of a large revolv- 
ing drum the interior of which has a number of oak pins 
attached securely to it, and so arranged as to soften the skins 
as they fall upon them, or in other ways continually come in 
contact with the pins. The number of skins placed in a mill 
of this kind at one time is from one hundred and fifty to two 



HIDE-MILLS. 251 

hundred, and the Morocco tanners at Lynn, Mass., and other 
places in New England where it is used, call it a " pin-mill." 

The Morocco tanners of Philadelphia, Penna., employ, some- 
times, a softening mill for the dry skins of a very different con- 
struction, which consists of a central, vertical, or upright shaft, 
on the top of which is keyed a beveled-wheel, which meshes 
with a suitable pinion. About two feet above the socket in 
which the upright shaft revolves, and passing through and 
secured firmly to the main shaft, is a second shaft about four- 
teen feet long, and extending horizontally at right angles with 
the upright shaft so as to divide itself into two arms of equal 
length. About one foot from the end of each of these arms 
there is an iron collar secured to the shaft, and against each of 
these collars a large granite roller, about four feet in diameter 
and eight inches face, is rested : the ends of the projecting arms 
of the horizontal shaft passing through the centre of the stone 
rollers, which are held in place by large iron washers which 
play loosely on the shaft against a steel pin. 

A pit is excavated about three feet deep, following the circle 
described by the inside vertical face of the two stone rollers. 

The socket in which the main or upright shaft revolves is 
placed on a level with the bottom of the stone rollers, and is 
supported upon a pedestal firmly planted in the centre of this 
circular pit. 

A workman stands in this pit and arranges the skins under 
the rollers as they revolve, sometimes exposing the flesh side 
and at other times the hair side to the rollers, and all the while 
keeping them moistened by throwing water upon them, 
which he obtains from the bottom of the pit in which he is 
standing. 

Mills of this kind may have theiradvantagesforsofteningskins, 
or they would not be employed by some of the largest Morocco 
tanners in this country; but they are to my mind both clumsy 
and dangerous, as it is simply a question of time when one or 
both hands or arms of the workman who attends them will be 
crushed by the rapidly revolving stone rollers, and the skins 
are constantly exposed to injury by remaining too long in one 
position under the rollers. 



252 



THE MANUFACTURE OF LEATHER. 



The hide-mills in common use, such as that shown in Figs. 65 
and 66, are lined with iron, and when properly constructed and 
cared for will wear for a long time. 

The hide mill is not a new idea, but was patented in this 
country in 1812 by Wm. Edwards, of Northampton, Mass. 

Mr. Edwards was also the inventor of the rolling contrivance 
now so commonly employed for rolling sole leather, both of 
which inventions have of course been greatly improved since 
his time. 

The idea of the hide-mill is primarily due to the falling 
machine, of which it is a reproduction with but slight modifi- 
cations, and to trace out the origin of the fulling machine would 
carry us far back near to the early dawn of history. 

A representation of the fulling process is shown on a tomb at 
Beni Hassan of about the time of Osirtasen, who is supposed to 
be the Pharaoh who invited Jacob to Egypt and settled him in 
Goshen. In this picture the roll of cloth is wetted and manipu- 
lated between a block and a concave inclined table, which table 
is very similar to the one-half of the trough of our hide-mills, 
and the water from the wetted cloth is represented as passing 
into a trough at the bottom of the table. 

The hide-mill shown in Figs. 65 and 66 can be employed for 
softening all kinds of hides and skins ; when used for cleansing 

Fig. 65. 




and softening sheep skins in the wool, the screen arrangement 
underneath can be used to save all the wool that becomes loosened. 

Fig. 65 is a top view. Fig. 66 is a vertical section of the mill. 

The hides or skins are treated by placing them in the reser- 
voir A, of the mill, the beaters of which are represented at B B'. 

The beaters have arms, E E, extending downward from them, 



HIDE-MILLS. 



253 



and being jointed to connecting-rods F F^ applied to bell-cranks, 
O (r, of a shaft H^ which shaft imparts a reciprocatory vibrat- 
ing motion to the beaters when it revolves. An improved 
method for connecting the pitman to the beaters is shown in 



Fig. 66. 




Fig. 67. After the reservoir or trough of the mill has been 
charged with the hides or skins, and the beaters set in motion, 
water is let into the trough. "Whenever sheep-skins are being 
operated upon, there is placed, as has been mentioned, under- 
neath the reservoir or trough, a frame, D^ covered with woven 
wire, and as the wool is worked from the skins it is washed 
through the opening C, and lodges upon the screen, and in this 
way a large quantity of fine wool is saved. 

The improvement in hide-mills, shown in Fig. 67, is the joint 
invention of Friend and Annable, and relates to the method of 
connecting the pitman, which actuates the beater of the mill, 
with the vibrating arm upon which the beater is hung (below 
the beater), in such a manner tliat the connection is made more 
perfectly than heretofore, and the parts may be tightened or 
adjusted from the top of the beater with less difficulty and 



2oi 



THE MANUFACTUKE OF LEATHER. 



trouble than is the case with the usual method of adjusting the 
parts. 

The invention consists, for this purpose, in making the connec- 
tion of the pitman and vibrating arm by means of a strap, which 
passes through or around the vibrating arm, having a bearing 
for the end of the pitman on one side, and a gib and key on the 



Fig. 67. 




other side, the key passing up through the beater, and adjusted 
by means of a nut on the top of the beater ; and in carrying an 
oil-tube from the working parts up through the beater, so that 
the connections may be lubricated. 

The invention is designed to overcome the difficulties and im- 
perfections of the common method of adjusting the parts before 
described in hide mills. As usually constructed and operated, 
it is very difficult to get at the connections for the purpose of 
taking up the wear which is the result of the continual jar and 
vibration. 



HIDE-MILLS. 255 

It has been found from experience that it is essential to make 
this connection below the beater, and consequently, below the 
hide-box, and from this cause, whenever the connection wears 
loose, there are no adequate means for readily adjusting it, and 
no method of lubricating the wearing parts. The wear is thus 
much greater, and there is more danger of injury to the mill 
from this cause. 

All the filth from the hides which are being milled passes down 
into the cavity below the hide-box, where these connections are 
located, making it a very disagreeable process to keep the con- 
nections in order, or to get at them for lubrication. 

The present invention for making these connections avoids 
most of these difficulties by making the parts adjustable and 
capable of being lubricated from the top of the beater, and the 
result is that the mill operates more perfectly, with less wear 
and injury to the moving parts, and with greater economy. 

Fig. 67 represents a vertical section of the beater, the lower 
part of the vibrating arm, and the parts employed in the new 
method of making the connection. 

A represents the vibrating arm. B is the beater, which is 
attached to the vibrating arm in any suitable manner. Cisa 
key, which passes through a slot in the strap D^ up through the 
beater to the top, where it is adjusted by a nut. The lower 
part of the key G is wedge-shaped, to correspond with the shape 
of the gib H. 

The strap D is made of iron, or other suitable material, and 
passes through the vibrating arm. It has a bearing, E E^ on 
the side opposite the key C, for the purpose of holding the end 
of the pitman F. This bearing is made wider than the strap 
D, for the purpose of shouldering against the side of the vibra- 
ting arm. 

G is an oil-tube, which passes down through the beater B, 
through the strap D, and into the bearing E. 

When the pitman i^becoraes loose from wear or other causes, 
it is only necessary to tighten the nut on the top of the beater, 
which raises the \.qj G, drawing the strap through the vibra- 
ting arm, and tightening the bearing E E, which incloses the 
end of the pitman. 



256 



THE MANUFACTURE OF LEATHER. 



The mill shown in Figs. 68 and 69 is for softening hides, and 
also for fulling cloth, and the invention consists in making the 
bed and back in two pieces, hinged or otherwise connected, 
and also in combining steam-chambers with the bed and back 
pieces, and furthermore in the form or shape of the back-piece, 
and in making it adjustable. 

Fig. 68. 




Fig. 69. 




Fig. 68 is an elevation in cross-section. Fig, 69 is a perspec- 
tive, partly in section, of the back and bottom pieces. 

A is the bed piece ; B, the curved slotted guides of the levers 
a a of the beaters G C. The slotted guides are provided with 
rubber packing or cushions to deaden the fall of the levers 
when there are not enough hides in the mill to receive the full 



HIDE MILLS, 257 

Stroke of the beaters. D is the cam-wheel which operates the 
beaters, b represents a chamber, which is cast or formed in the 
bed piece, making part of the same, to which steam is to be 
introduced through suitable pipes. To the end of this bed 
piece is hinged or otherwise arranged a curved adjustable back, 
JE, having also cast or formed in its back or rear a steam-cham- 
ber c, the object of both being to apply heat through the iron 
bed or back piece to assist the beaters in softening the hides. 
Making the bed and back pieces in two parts produces an im- 
portant effect, viz., to permit of the adjustment of the back, 
which is accomplished by hinging it to the bed piece (shown at 
e), and by back bolts c? d, which pass through the side pieces F 
of the frame, which hold the back at any angle desired. This 
adjustment allows the operator to turn the hides, by the action 
of the beaters, faster or slower, as they may require, and to 
turn hides of different grades as regularly and evenly as though 
they were all alike. Hard flint hides require, in order to be 
worked equally well, the back of the mill to be at a different 
pitch or angle than for soft hides. The shape or peculiar curve 
of this adjustable back U is also a very important feature of 
this invention, and it has been a work of great difficulty to 
arrive at the right form, so that the hides will gradually and 
regularly, by the action of the beaters, be turned over and over, 
so that each and every part of the hides will, in turn, receive 
the strokes. A slight change in the curve or shape of the back 
would result either in the contents of the mill not turning over 
at all, or, after turning a time, they would wedge fast in the 
bottom of the mill, which would necessitate stopping it and re- 
adjusting its contents. The peculiar form of this back piece F 
and its adjustment to the bed piece A cause the beaters to 
turn the contents of the mill completely over with a few or 
many strokes, at the option of the operator. It is claimed that 
this mill is self-acting, requiring neither tending nor watching. 
Its use for softening hides should be found very important, as 
they can be manipulated and softened, it is claimed, in a better 
and in a much shorter space of time than with ordinary mills. 
When used for this purpose, iron pins are inserted in the heads 
17 



258 



THE MANUFACTURE OF LEATHER. 



of the beaters. This mill can be made entirely of metal, thus 
adding to its strength and durability. 

The hide-mill shown in Figs. 70, 71, 72, and 73 is the inven- 
tion of Middleton, and he claims that his improvements in 
machinery for stocking, unhairing, and softening hides, skins, 
and leather have the effect of rendering the machines capable 
of operating much more quickly upon the leather, hides, or 
skins, consequently doing a greater amount of work. The 
number of strokes or blows of the machine per minute upon 
the leather or hides may be varied, as also the strength or force 
of the blows. 

Fig. 70 is a part longitudinal section. Fig. 71 a part trans- 
verse section. Fig. 72 a plan looking at the top, and Fig. 73 a 
front elevation of part of machine to be described hereafter. 



Fig. 70. 




Fig 


.71. 


ht- — 




Vra?| 


}|ip)) 


f?il 




\l3^ 


rT^ ^ i 



The inventor places two steam-cylinders a a, on a founda- 
tion-plate b, side by side, so as to act direct upon the stock-feet 
c c, which are coupled to the end of the piston-rods d d! by 
means of ordinary cotters e, as shown. Motion is imparted to 
the pistons, which are within the cylinders and of ordinary con- 



HIDE MILLS. 



259 



struction, by steam, which is admitted thereto through ordi- 
nary shde-valves by means of a variable valve-motion, //' being 
the valve-spindles, each being actuated by means of a sliding 
cam g^ through oscillating levers h and i. The required 



Fig. 72. 





motion is transmitted to the cam from one of the piston-rods 
Co, through lever j and connecting rod h. The motion of the 
cam y is varied by a self-acting ratchet arrangement. 

Every stroke of the pistons carries the lever / with them, 
from which an intermittent motion is transmitted to the bevel- 
wheels I and V through the rachet-lever m, pawl n, and rachet- 
wheel n'^ the bevel-wheel I being fitted with sliding key on to 
the screw a, on which, also, is provided the nut p. On a rotary 
movement being given to the screw o a traverse motion is im- 
parted to the nut ^, which carries with it the rachet-gearing, 
and lever w. also varies the position of the end ¥ of the con- 
necting-rod k in the slot/ of the lever/, which has the effect of 
varying the traverse of the cam c/, and thence the motion of 
the slide-valves employed for admitting steam into the cylin- 
ders ; also, by this motion the steam is exhausted at variable 
points of the piston's stroke. The object of this variable move- 
ment is to cause the stroke of the feet of the stocks to be more 
or less effective, consistent with the proper working of the 
leather, hides, or skins. 



260 THE MANUFACTURE OF LEATHER. 

As well as the above automatic arrangement of varying the 
stroke, it may also be varied by the hand of the attendant. 

In order to effect a regularity of stroke of both piston-rods d 
and cZ', the inventor applies a provisional tappet-motion on the 
piston-rod d'. The position of the clamp or tappet q may be 
adjusted and fixed in any required position on the piston-rod d\ 
and in the event of the stroke of the piston-rod d' differing from 
that of the piston-rod c?, the clamp or tappet q comes in contact 
with one of the collars r or / on the rod 5, which is mounted in 
suitable bearings t^ causing it thereby to move either right or 
left, which movement is transmitted to the slide-valve spindle 
/', causing thereby the valve to be moved and the stroke of the 
pistons to be reversed. This arrangement only comes into 
operation when any irregularity occurs, and has the effect of 
preserving the stroke of each piston the same. 

The inventor also conducts the exhaust-steam into jacketed 
ends u, of the frame-work, suitable openings being provided for 
the admission and exit of the same, and the steam supplies an 
inexpensive artificial heat to the stocks for the purpose of 
quickening the process. 

List of all Patents for Hide Mills, issued hy the Government of the 
United States of America, from 1790 to 1883 inclusive. 



No. 


Date 




Inventor. 


Residence. 




Dec. 30, 


1812. 


Wm. Edwards, 


North Hampton, Mass. 


66,294 
Reissue 

2,727 


)july 2, 
j Aug 3, 


1867. 
1867. 


> J. M. Brown, 


Boston, Mass. 


100,519 


Mar. 8, 


1870. 


J. P. Friend and 
B. R. Annable, 


Peabody, Mass. 
Salem, Mass. 


109,393 


Nov. 22, 


1870. 


J. G. Curtis, 


Emporium, Pa. 


125,135 


April 2, 


1872. 


S. Hussey, 


Gowanda, N. Y. 


221,246 


Nov. 4, 


1879. 


R. Middleton, 


Leeds, England. 



THE LIMING PROCESS. 261 

List of all Patents for Breaking Hides, issued hy the Government of 
the United States of America, from 1790 to 1883 inclusive. 



No. 


Date 




Inventor. 


Kesidence. 




Dec. 22, 


1826. 


H. C. Clark, 


Randolph Co., N. Y. 




Feb. 13, 


1833. 


B. Aylsworth, 


Masonville, N. Y. 


229 


June 10, 


1837. 


E. Kendall, 


Newton, Mass. 


6,710 


Sept. 11, 


1849. 


I. S. Heershey, 


Hagerstown, Md. 


7,281 


Apr. 16, 


1850. 


C. Bauchman, 


North Whitehall, Pa, 


92,776 


July 20, 


1869. 


0. W. Bean, 


Farmington, Tex. 


107,562 


Sept. 20, 


1870. 


E. D. Taylor and 
Wm. Rude, 


Hornelsville, N. Y. 


199,415 


Jan. 22, 


1878. 


^ 




202,414 


Apr. 16, 


1878. 


> Wm. Coupe, 


South Attleborough, ' 


241,308 


May 10, 


1881. 


) 





CHAPTER XY. 

PROCESSES AND COMPOUNDS FOR DEPILATING HIDES AND SKINS 
—THE LIMING PROCESS — OTHER DEPILATORY COMPOUNDS AND 
PROCESSES — DEPILATING BY SWEATING — THE COLD SWEATING 
PROCESS — THE WARM SWEATING PROCESS — OBSOLETE METHODS 
OF DEPILATING — LIST OF AMERICAN PATENTS FOR COMPOUNDS 
FOR DEPILATING HIDES AND SKINS. 

Section I. The Liming Process. 

Depilation or " unhairing" is the process of removing hair 
from hides and skiiivS, and wliile there are many methods for 
accomplishing this result it is commonly achieved by placing 
them in a solution of lime until the hair bulb is loosened, thereby 
allowing the hair to be readily rubbed or scraped off'. 

The use of lime is often inconvenient and in many ways 
unsatisfactory, as owing to the energetic action which free lime 
exerts on animal tissues, a considerable portion of the gelatinous 
tissue of the hide is disintegrated and decomposed during the 
liming process, being removed from the hide in the form of 
soluble gelatine, or else so altered as to be rendered incapable 
of combining with tannin, thereby incurring a serious loss in 



262 THE MANUFACTURE OF LEATHEK, 

the weight of leather that should be produced, and in its quality, 
as the skins or hides treated by this process produce leathers 
less supple and more brittle than is desirable. 

These objectionable results are more of a physical than of a 
chemical character; the principal modifications of the chemical 
constitution of the hide or skin treated by the lime process is 
the slight increase in the quantity of lime which it originally 
contained, and a decrease in the quantity of fatty matters due 
to the saponification caused by the lime; the harshness and brit- 
tleness imparted to the leather being caused not only by the 
saponification of the fatty matters, but much more so through 
the presence of the quantity of lime which penetrates into the 
tissues. 

Suppleness being an indispensable requisite for upper, 
Morocco, and other kinds of leathers, it is restored to them after 
being treated by the lime process by subjecting them to the 
action of a bating process, performed by immersing the hides or 
skins in a solution of hen, pigeon, or dog manure, and various 
other solutions which will be enumerated in Chapter XVII. 
the object of such treatment being to neutralize the lime con- 
tained in the tissues. 

This "bating" is usually performed in consequence of the 
employment of lime for depilating, and as both of these processes 
are expensive and add largely to the cost of producing all 
classes of pliable leathers, it is much to be desired that some 
substitute for lime should be found which would be generally 
acceptable to tanners, and obviate the bating process as well as 
lessen the expense of unhairing hides and skins. 

From the large amount of attention that is being given to the 
subject of depilating, both in this country and in Europe, and 
from the tendency of the age to cheapen all the manufactured 
products of general consumption, we are probably safe in saying 
that the time is now near at hand when the slow, inconvenient 
process of depilating by lime must be succeeded by more effec- 
tive, rapid, and economical methods. 

Some of the inconveniences of the liming process we reca- 
pitulate as follows : — ■ 

1st. The contact of caustic lime alters more or less the tex- 



THE LIMING PROCESS. 263 

ture of the hide, and permitting it to penetrate the pores, it 
remains in them in the state of caustic lime, carbonate, or lime 
soap. 

2d. The rinsings in water, bating, and the workings remove 
it only partially, leaving an impediment to thorough tanning. 

3d. It also hinders the ready penetration of the tan liquor, 
and the perfect combination of tannin with the skin, and so 
obstinately resists removal during all manipulations that a 
portion is always found in the best leather. 

These disadvantages have already led to numerous efforts for 
the substitution of other agents, which we will enumerate later 
in this chapter. 

The present process to which hides are subjected is termed 
" raising," and by it the pores are distended, the fibres swollen, 
and the hair loosened. These results are effected by means of 
alkaline or acid solutions, and by sweating or fermentation. 
Milk of lime, as we have stated, is the alkaline liquor generally 
employed. Lime-water has been proposed as a substitute, but 
it is less permanent in its action, and requires frequent renewal 
in order to insure the perfect cleansing of the hides. 

The primitive manner of removing the hair was to shave it 
off, but lime was employed even by the early Egyptians. The 
depilating process in addition to swelling the hide, thereby 
loosening the hair and disposing it to yield readily to the 
depilatory operation, also facilitates, by opening the pores, the 
absorption of the tannin. 

If there is a desire to tan quickly, and produce good and 
heavy leathers, it is highly important that the hides or skins 
should be properly prepared in the beam-house. As the after 
results depend largely upon the intelligent care bestowed here, 
much more attention should in practice be given than most 
tanners are inclined to grant. 

All hides that are intended for limed stock should be put in 
the right condition for the lime — that is, soft enough, but not 
flaccid — as dried skins may be greatly injured by being softened 
too much. A hide fresh from the animal is the best criterion 
as to the condition, for in that state it is best suited for the 
lime. 



264: THE MANUFACTUEE OF LEATHER. 

When placed in the lime they should be frequently handled 
or agitated, and should remain in the solution no longer than 
may be necessary to loosen the hair in order that it may be 
readily removed. 

The ancients and those whom progress has failed to reach 
said, and say still, who limes, tans ! Any tanner who entertains 
such ideas tans his stock without a thought of the difficulties 
he is creating for the currier. 

Lime is a factor, useful and hurtful at the same time, and it 
therefore becomes necessary that the tanner should occupy 
himself actively with the conduct and the good management of 
his lime-pits, and he should in case of necessity entrust this 
work only to a reliable man, a good workman. 

Most tanners neglect their work at the lime-pits; and when 
our American calf-skin tanners fully realize this point and shall 
take care of their lime-pits, and see to the intelligent beamwork 
of their stock, they will produce calf-skins of the first quality, 
for we possess better bark for this work than can be found in 
Normandy or any portion of France. 

We shall diverge for a moment and speak of the proper 
treatment of calf-skins in the limes. When the slaughtered 
calf-skins peel they should be immediately taken out of the 
lime. After having allowed them to drip well, put them in a 
vat with enough water to cover them without floating. They 
thus undergo a first disgorging; they may, if necessary, re- 
main in this water for eight or ten days without spoiling. 
This method is preferable to piling, for while in the water the 
skins disgorge and the action of the lime is weakened, and in 
the pile the lime continues its action, and if workmen in piling 
are not careful to open them evenly,- the skins get what the 
curriers call " lime folds," which are almost impossible to eradi- 
cate in currying. But best of all, as soon as the skins peel, take 
them out of the lime-pits, rinse them and unhair them at once, 
as promptness in the execution of labor is an economy of capital. 
From this first stage the work must go on as fast as possible. 

Salted calfskins after being properly soaked should be put 
into the dead lime-pit, and afterwards treated the same as 
slaughtered stock from this point; but the dry skins require a 



THE LIMING PEOCESS. 265 

milder lime-liquor than the salted skins and the fresh slaughtered 
stock. This work is thus rendered a little slower on account 
of the lime-liquor in the dead lime-pit having been previously 
carefully weakened. 

Lime in depilating has been at times replaced by acid liquors ; 
but their employment requires the exercise of judgment. 
The dilute mineral acids make the hair yield easily ; but at 
the same time they swell and soften the hide too much, so that 
the use of organic acids is preferable. In some tanneries lime 
is replaced by a mixture of slacked lime and ashes. Through 
the mutual action of the lime and the carbonate of potassium 
a caustic alkali is formed, which operates more energetically. 

Lime-vats are constructed either of timber or of masonry, 
and in tanneries where hides are worked they are sunk into the 
ground so that the tops of the vats are on a level with the floor 
of the beam-house ; but in goat and sheep-skin tanneries the 
vats are partly below and partly above the level of the floor, 
as shown in the view of vats in Figs. 236 and 263. 

The vats destined to swell the hides to facilitate the depilation 
and raising are usuall}?" constructed so as to take sides instead of 
whole hides, the hides being usually split after soaking, which 
answers for upper leather ; but it is very much better for the 
stock that is intended for sole, belt, and harness leather to lime 
the whole hides and then to split them into sides after liming. 

When split previous to liming the thin portions of the hide, 
shoulders, etc., contract to a much greater degree than the 
butts and other thicker portions, and consequently the back 
line is irregular, which would not be so noticeable if the 
lime had uniform action on the whole hide, thus economizing 
the waste in cutting harness leather, but more especially belt- 
leather, where straight back lines are very desirable. 

The number of hides determines ordinarily the quantity ot 
lime necessary for each vat. To make a new vat throw into it 
unslacked lump lime, cover with water gradually so as not to 
drown it, and stir well with a " stirrer" until slacked and reduced 
to the consistence of milk. This operation completed, leave it 
until it is ready to receive the hides. Sometimes the lime is 
prepared in a hogshead, and from this poured into the vat, care 



266 THE MANUFACTURE OF LEATHER. 

being observed to retain the sediment in the bottom of the 
hogshead, which keeps the lime vats cleaner and is beneficial 
in many respects. The vats are distinguished as dead, weak, 
and live vats, and sometimes as old and fresh limes. The dead 
or old vat is that which has been frequently used and which 
has been nearly exhausted of its strength, the weak is that 
which has been used long enough to deprive it of a portion of 
its force, and the live or fresh vat is that which has not yet been 
worked. 

It is easy to understand that the live vat becomes successively 
the weak and the dead vat. When a tanner uses more than 
three vats he establishes between the dead and live vats as 
many middling terms vats as convenient and the whole of the 
vats are called the raising series. 

The raising should be commenced in the dead vat, and con- 
tinue in consecutive order through the series to the live vat. 
In some tanneries in Europe the series consists of twelve or 
more vats ; and in that case there should be a graduation in the 
strength of the liquors. The duration of this operation varies 
in different localities, as in all portions of Europe the hides are 
limed for a longer period than with us. 

The practice is still in vogue among some tanners of using 
old limes which are charged with the decomposing matter ex- 
tracted from previous packs, which practice, in warm weather, 
beconies extremely hazardous. 

The time usually employed for liming different classes of 
hides and skins will be mentioned in the chapters devoted to 
the manufacture of sole, upper, calf, Morocco, and other 
leathers. 

The reel is now generally employed for handling in the lime- 
vats and it is the most economical, convenient, and effective 
method, the sides being strung together, and passed over the 
reel from vat to vat. 

Steinmann's apparatus for handling hides in the lime-pits is 
shown in Figs. 74 to 77. 

Fig. 7-i represents a pit furnished with this contrivance. 
Fig. 75 is a vertical section in the plane of one of the spikes. 



THE LIMING PROCESS. 
Fig. 74. 



267 




Fig. 75. 



Fig. 76. 




-\v\\v\^ 




Fig. 77. 




F , 



268 THE MANUFACTUKE OF LEATHER. 

Fig. 76 is a vertical section of the operating jack or gear-work. 
Fig. 77 represents, on a larger scale, a form of lever, pawl, and 
ratchet movement adapted for use with such apparatus, one in- 
closing-plate being removed. 

The pit A may be of any suitable form, from the bottom of 
which there rise two spikes, B B, with the points curved 
somewhat toward the interior of the pit, which makes it much 
easier for them to engage and disengage the hides than if they 
were straight, and besides the hides are in much less danger of 
injury. In other contrivances of a similar character blocks are 
sometimes used, having a roller on each side of the spike, and 
it has been found, in practice, that blocks thus constructed are 
liable to bind and hitch in the operation of hoisting the hides. 
It has also been found that portions of hide and hair would 
lodge in the unprotected rollers, and clog them to such an ex- 
tent as to render the device nearly inoperative. But Mr. Stein- 
mann claims to remedy both these defects by constructing the 
frame of the block in the form of a tube or sleeve (7, half of 
which, c, is semi-cylindrical, and closely hugs one side of the 
spike, while the other half is made of proper form and dimen- 
sions to contain two rollers, I) D'^ journaled, one vertically over 
the other. 

Extending from the upper part of each- sleeve or block is an 
eye, E^ for engagement of the hook on the extremity of a chain 
F^ attached to a windlass, operated by a lever and ratchet and 
gear movement. 

A suitable step or bearing, H^ affords journal-bearing for the 
windlass- shaft, which shaft carries a spur-wheel, /, that gears 
with a pinion, J, on the ratchet-shaft K^ to which shaft is per- 
manently fastened a ratchet-wheel, L. A lever, if, having a 
pawl, N^ engages in this wheel. A tentative pawl, P, pressed 
by a spring, 0, prevents any retrograde rotation of the spur- 
wheel /, and thereby enables the windlass to hold the hides to 
the degree of elevation desired, or, being released, permits the 
parts to " run down," and the hides to descend by their weight 
to the bottom of the pit. The length of the lever and the ex- 
cess of diameter of the spur-wheel /over the pinion ./impart 
so high a purchase that one man can do the work of two or 



DEPILATOEY COMPOUNDS, 269 

more under tlie plan of previous contrivances of a similar char- 
acter. 

Fig. 77 sliows the preferred form of operating lever, pawl, 
and ratchet ; L represents the ratchet-wheel, having a central 
orifice, /;, whereby it is fitted and keyed fast to the shaft of the 
windlass-cylinder. R is the lever-socket, sleeved, and capable 
of revolving upon a boss of said wheel. (Shown by dotted 
line.) iV^is a pawl, held to the position shown, or to the reverse 
position, or to one just intermediate, by spring-follower S. If 
it is desired that the lever M should feed in the opposite direc- 
tion, the pawl is reversed, and the tentative pawl P is applied 
on the other side. If it is desired that the lever should be in- 
operative, so as to allow the hides to descend freely into the 
pit, the pawl N is placed so that its apex n will engage with 
the notch s of the follower. 

In some tanneries in the -West an apparatus is employed for 
liming hides which was invented in 1865, by Mr. Wra. H. 
Study, of Economy, Ind. ; the contrivance consists of a rotary 
rack, so applied to a shaft as to adjust the distance and adapt 
the racks to hides of various sizes. 

The frame used in conjunction with the rack is so arranged 
as to be readily raised or lowered, and the bottom of the liming 
vat in which the racks revolve is concave. - 

Section II. Other Depilatory Compounds and Processes. 

Rohinsoii's Process. 

This process consists in loosening the hair or wool from hides 
or skins by the direct application of steam thereto while sus- 
pended in any suitable apartment to which steam can be ad- 
mitted. 

Ward's Process. 

This method consists in the application of a compound solu- 
tion of carbonate and sulphate of soda. 



270 THE MANUFACTURE OF LEATHER. 

Wikon's Process. 

In this method the depilatory compound is composed of 3 
gallons of lime, 2 ounces of potassium, 2 quarts of strong soft 
soap, 2 ounces of ammonia, and 3 ounces of sulphur to each 
100 gallons of water. 

This composition it is claimed will start the hair in two 
days. 

Carter and KeitKs Process. ' 

This is a solution composed of one barrel (33 gallons) of 
water, in which are dissolved sal-soda, carbonate of potash or 
common lye 11 pounds ; prussiate of potash or nitrate of soda, 
11 ounces; common salt, 11 ounces; lime, 22 pounds. 

De Montoisoii's Process. 

This process consists in subjecting the skins to the influence 
of a solution consisting of hydrate of lime, sulphide of barium, 
sulphide of arsenic, potash and hydrosulphate of soda, or other 
form of alkali. 

Head's Process. 

In this method the hides are placed in a vat about 8 feet long, 
4 feet wide, and 4 feet deep, containing water into which has 
been poured a mixture of about one and one-half bushels of sal- 
soda, and one bushel of quicklime, which composition it is 
claimed will shorten the time for liming the hides to about six 
hours. They are afterwards soaked in a vat of water at a 
temperature of about 110° F. for two hours and then unhaired 
and lime shaved. 

Depilating loith Steam in a tight Room or Vat, 

The following method of depilating was invented by Banks. 

After the hides are softened in the usual way they are sus- 
pended in a tight room or vat, and subjected to the action of 
steam at a temperature not exceeding blood heat. This process 
is to be continued in warm weather about four days and in cold 



DEPILATORY COMPOUNDS. 271 

weather about seven days, when it is claimed the hair can be 
easily and readily removed. 

The inventor states that this method of unhairing is to be 
applied only to those hides that are to be manufactured into sole 
leather. 

Depilating hy the use of Soda-ash^ Caustic Lime^ Monosulphuret 
of Potassium, Hard Soap^ and Soft Water. 

For depilating a pack of fifty sides of cow hides, or one hun- 
dred and thirty calf skins : — 

Take fifteen pounds of soda-ash, thirty pounds of caustic lime, 
stir them in ten gallons of soft water, and boil the mixture in 
an iron or other suitable vessel for one hour ; let the solution 
become cold and then add one pound of sulphuret of potassium 
dissolved in water, and stir the whole thoroughly. 

The next thing required is a vat of suitable capacity to 
receive the pack of hides or skins, with a sufficient quantity of 
soft water to cover them. 

Into this vat of water a small quantity of the preparation 
before described should be poured, and the vat well stirred. 

If the attendant by dipping his finger into the vat and ap- 
plying it to his tongue does not feel a sensation and taste pecu- 
liar to the alkali, more of the solution must be added until the 
strength of the liquor is sufficient to produce these sensations. 

Two or three pounds of hard soap may now be dissolved in 
water, added to the liquor and well stirred, which completes 
the preparation of the vat, and the hides or skins are to be 
placed in it, and agitated frequently in order to expose every 
part of them thoroughly to contact with the liquor. 

Mr. A. K. Eaton, of New York City, who invented and used 
this process for a long period, states that in order that the hides 
or skins may not be too much plumped for the first twenty-four 
hours, the strength of the liquor up to the end of that period 
should not be increased ; but after that it may be gradually 
strengthened as the process advances, and until it is completed, 
which will be in from two to four days according to circum- 
stances, when the hair will come off very readily. By increas- 



272 THE MANUFACTURE OF LEATHER. 

ing the proportion of the sulphuret of potassium, the time re- 
quired for the process will be correspondingly shortened. 

The labor involved in this process is comparativelv slight, 
the stock, it is claimed, is in a better condition for being treated 
with the tanning agents, and it is also claimed that it is heavier 
than when the ordinary depilating process is employed, as less 
gelatine is dissolved. The leather when finished, it is also 
claimed, is closer grained, more flexible, as well as more dura- 
ble, and less pervious to water when the skin is unhaired by 
this process than when unhaired by a process that dissoHes 
more of the gelatine, as the texture is less open and the leather 
not so spongy. 

The sulphuret of potassium, before mentioned, may be pre- 
pared as follows : Take equal parts by measure of finely pul- 
verized charcoal and sulphate of potash, mix them thoroughly 
and expose them to a dull-red heat for an hour in a covered 
crucible, the product will be the sulphuret required, 

ComjDosition for Depilating Green and Dry Hides^ with Nitrate 
of Potassa^ Chloride of Sodium^ Sulphuric Acid, and Tartaric 
Acid. 

Hides may be depilated in an easy and expeditious manner 
and it is claimed without injury, and so as to produce a greater 
percentage in the weight of the leather than is possible by the 
ordinarj^ means, by the use of the following composition: One- 
quarter of a pound nitrate of potassa, one quart chloride of 
sodium, four and a half pints sulphuric acid, one ounce tartaric 
acid, or, in lieu thereof, one pint of vinegar, twelve pounds of 
wheat-bran, and five hundred gallons of sour or spent tan-liquor. 
These ingredients are properly commingled and then applied to 
the depilation of dry or imported hides in the usual manner. 

In treating green hides the first two ingredients, nitrate of 
potassa and chloride of sodium, and the wheat-bran, are omitted 
from the composition, their functions being solely to soften the 
hard, dry imported hides, and reduce them to a condition simi- 
lar to the normal condition of the green hides. It is claimed 
by Mr. Peter G. Schlosser, of Middletown, Frederick Co., Md., 
who discovered this composition, and who proved it by a long 



DEPILATOEY COMPOUN"DS. 273 

course of experiment and trial to be a very valuable one for 
the purpose above specified, that the injurious consequences re- 
sulting from the use of lime for that purpose are avoided, the 
substance of the hide itself not being eaten away and destroyed, 
as it oftentimes is when lime is employed. But all the body 
and strength are preserved, and a greater amount of leather is 
produced than it is possible to obtain when lime is used. Be- 
sides this it is also claimed that the time heretofore consumed 
in "bating" or cleansing the hide from the lime, which was 
very great, and the labor are entirely saved, and the whole 
process of preparing the material for tanning is in that degree 
shortened. Mr. Schlosser also claims that by this process 
twenty-five pounds of dry hide will produce about forty pounds 
of leather, and one hundred pounds of green hide will produce 
about seventy pounds of leather. 

The employment of Sidphuretted Hydrogen Gas in connection 
xoitli Lime^ Soda-ash, etc., as a Deiyilatory, and for the purpose 
of Swelling Hides, 

The object of this compound is to depilate and raise hides 
and skins preparatory to tanning, thus dispensing with milling 
and breaking. 

In order to accomplish this the inventor, Mr. George W. 
Adler, of Philadelphia, Pa., uses a compound consisting of gas- 
lime, that is lime charged with sulphuretted hydrogen gas, 
which is the refuse lime of gas-works, an alkali, such as soda, 
potash, pearlash, or soda-ash, pure lime and an oil, and he also 
claims that this compound acts as a preservative as well as a 
depilating and raising agent. 

The proportions are as follows : Of lime, pure unslacked or 
slacked, two bushels; of soda-ash, or any other alkali, fifty 
pounds ; of oil, either vegetable, fish, animal or mineral, two 
and one-half gallons ; .and of gas-lime, or lime charged with sul- 
phuretted hydrogen gas, two bushels, or enough to make a 
solution of the required strength as a depilatory. 

In mixing or forming the compound, take the gas-lime and 
add sufficient water to make a solution, then take the two 
bushels of lime and slack, after which add the fifty pounds of 
18 



274 THE MANUFACTUKE OF LEATHER. 

soda-ash, or other alkali, and dissolve it in water, or add the 
soda-ash or other alkali direct to the solution, now add the two 
and one-half gallons of oil, and mix the whole together, so that 
they will be thoroughly incorporated. 

The compound is now ready for use, and is applied according 
to the judgment of those skilled in the art of treating or tanning 
hides and skins. 

When the gas-lime is added to water sufficient to make a 
solution it makes a most powerful depilatory, but this is of no 
use, except as a depilatory, until the soda or alkali is added, as 
a raising agent for the purpose of swelling the hides or skins ; 
the oil forms a basic or mineral soap in connection with the 
soda and lime, and it is claimed prevents the destructive action 
of the alkali upon the gelatine and tissues or fibres of the hides. 
Those who employ this method need not of course confine them- 
selves to the exact proportions which have been given, as this 
is a matter of judgment; but the formula herein given has pro- 
duced the best results in practice. 

A Compound of Potash^ Lime^ Salt and Sulphur^ and Charcoal 
for Depilating. 

After the hides are prepared for depilation by soaking, mill- 
ing, or breaking, in a proper manner, Mr. John Henry, of New 
York City, prepares and uses the following composition :— 

Into four barrels of water put five pounds of potash, ten 
pounds of lime, ten pounds of salt, one pound of sulphur, and 
one-half pound of pulverized charcoal ; having previously dis- 
solved the other articles in blood-warm water. 

The whole, which is sufficient for one hundred calf-skins, or 
an equivalent of hides, is then put into a revolving wheel, 
together with the skins or hides to be depilated, and the Avheel 
is made to revolve at the rate of twenty revolutions per minute. 

Mr. Henry claims that the skins or hides are, by the method 
above described, brought into direct contact, as to their whole 
surface, with the composition, and that, being agitated and 
kneaded, while in the composition, the process can be com- 
pleted in ten hours. 

He also claims that this composition is less injurious and 



DEPILATORY COMPOUNDS. 2iO 

more speedy in its action, and enables the skin or hide to be 
tanned more rapidly afterward than if lime alone were used. 

The Use of " Refuse Gas-Lime^'' as a Depilatorj. 

The bluish-green mass which is produced in the purification 
of illuminating gas, and which is considered a very obnoxious 
refuse by gas-makers, is generally known by the name of " re- 
fuse gas-lime." This substance, it is stated in the patent for 
the present process, consists of sulphide and sulphydrate of cal- 
cium, and small quantities of the lime salts of carbonic and sub- 
sulphurous acids. 

The first two named ingredients, sulphide of calcium and 
sulphydrate of calcium, render this substance applicable for the 
purposes of depilation. 

Mr. John E. Siebel, Chicago, 111., the patentee of the applica- 
tion of this waste product for depilating, states that mixed with 
water this refuse forms a mixture which, on account of its con- 
taining sulphydrate of calcium, he used as a cheap and effec- 
tive agent in tanning for freeing the hides from hair. For this 
purpose the refuse gas-lime, as soon as possible after it leaves 
the refining apparatus of the gas-works, is mixed with water to 
form a thick liquid, in which the hides are immersed until the 
hair is loosened, and ready for removal by the unhairing knife.^ 

1 I fail to see on what grounds a patent could be issued for this process, as 
Boettger had proposed the use of lime that had served for purifying gas, and 
the employment of this material for depilating purposes had been mentioned in 
technical books long previous to the date of this patent. See also Boettger's 
process for depilating with hydrosulphate of lime, described on p. 288. 

This material is a mixture of caustic lime, of carbonate, sulphite, hydrosul- 
phite, sulphate of lime, of sulphuret of calcium, of hydrosulphuret, of sulpliu- 
ret, and of cyanuret of calcium. The two last soluble salts especially act 
energetically on the hair bulb to dissolve it or to disunite it ; besides the gas- 
lime may be replaced by an aqueous extract of such lime. In order to avoid the 
inconvenience caused by the liberation of prussic acid, it is best not, immediately 
after the peeling by means of gas-lime, to submit the hides to the action of acid 
liquids. A mixture of nine parts of lime and of one part of oi'piment, which 
causes the formation of hydrosulphuret of calcium, may be used to peel the 
skins of small animals. 



276 THE MANUFACTURE OF LEATHER. 

Depilating with the Double Sulphate of Sodium and Calcium. 

This compound is the invention of Jules Watteau, of 
Antwerp, Belgium, and is intended to be used for facilitating 
the pulling of wool or hair from the skins of sheep or other 
animals. There are taken — 

38.50 parts, by weight, of carbonate of soda, 
38.50 parts of hydrated oxide of lime, 
13.00 parts of flowers of sulphur, 
6.50 parts of pulverized wood-charcoal, ' 

3.50 parts soot. 

These elements are pulverized and then intimately mixed 
together, and the mixture is boiled for about two hours, in a 
vessel containing about three times its weight of water, thereby 
producing a liquid of a dark-green color. This liquid, by 
means of a brush, is spread upon the fleshy side of the skin from 
which the wool or hair is to be removed. The skins are then 
placed in a pile, wool against wool, fleshy side against fleshy 
side, and after a few hours, it is claimed, that the wool can be 
pulled with the greatest facility without injury to the skin. 

The soot and charcoal are not essential parts of this composi- 
tion, but enter into it as inert matter, and so remain, as does 
also the carbonate of lime, which is one of the results of the 
combination above described. The liquid, it is claimed, de- 
rives its extraordinary depilating power from the resulting 
sulpho-sel or double sulphate of calcium and sodium. 

The inventor gives the proportions of the carbonate of soda, 
hydrated oxide of lime, and flowers of sulphur, which, in 
practice, he finds to be best ; but these proportions may vary 
considerably. 

The patent of Brainard, dated May 20, 1862, No. -35,293; and 
the English patent of Claus, 1906, granted in 1855 ; and the 
application of Lynds, filed in the patent office in September, 
1854, would appear to conflict with this invention, but the 
double sulphate of sodium and calcium is not obtained in any 
of the combinations and processes therein described. In one or 
more of them sulphide of sodium and sulphide of calcium are 
produced, but there is no chemical union between these two 
sulphides. 



DEPILATOEY COMPOUNDS. 277 

By boiling in water, however, as the inventor directs, there 
takes place, it is claimed, a chemical union not otherwise pro- 
duced, or not produced to so great a degree in any other man- 
ner. By the boiling the two sulphides are chemically united at 
the instant of their formation, giving the double sulphide. 

Depilating ivith Charcoal. 

In lieu of lime for removing the hair and cleansing the pores, 
charcoal may be employed either as a substitute for lime, or 
the hides or skins may be, as heretofore, first partly treated with 
lime and finally treated with charcoal. 

The carbonaceous matter employed may be either animal, 
vegetable, or mineral charcoal in suspension, and it is claimed 
by Mr. William Anderson, of Inverkeithing, near Edinburgh, 
Scotland, that the results of this treatment are that the hairs 
are loosened, the pores of the skins or hides purified, and the 
putrescent matter, grease, and other impurities removed. 

Mr. Anderson states that the most advantageous method of 
carrying this invention into effect is as follows : The hides or 
skins are placed in water of 60° F. with powdered wood-char- 
coal sufl5.cient to give it the consistence of cream, the hides or 
skins being removed and then placed back in the same liquor 
each day until the hairs are sufficiently loosened to yield easily; 
care being observed to stir the charcoal-powder which may have 
subsided in the intervals of removal, in order as far as possible 
to keep it in suspension. 

The hides or skins are afterwards washed, fleshed, and 
scudded as in the ordinary method, when they are ready for 
tanning without other treatment, and the charcoal-powder may 
from time to time be revivified by drying it in thin layers in the 
sun or in a current of air. 

In order to render them flat and soft, and to remove lime and 
other impurities from hides or skins, which may have been 
treated with lime for the purpose of removing the hairs, the 
process which has just been described may be applied. 



278 THE MANUFACTURE OF LEATHER. 

Maynard^s Method for Depilating hy the employment of Lime 
in Water, together ivith Suljohurous Acid. 

Liming hides, as we have seen, has been done by the use of 
lime simply, or lime and sulphur, potash, soda, arsenic, etc., alone 
or in combination, the time employed being of different du- 
rations. It is claimed by Maynard, the inventor of this process, 
that hides may be rendered fitfor depilation by its use in a very 
short period of time, and at but small expense. 

Maynard claims that the use of lime in water, together with 
snlphurous acid, causes the lime to seize hold of the oleaginous 
matter of the hide, producing a saponifying effect or giving a 
soapy feeling to the hide, and that by introducing sulphurous 
acid the sulphur and hydrogen attack the hair-bulbs, decompos- 
ing the sulphur contained in them, loosening and releasing the 
hair preparatory to depilation.^ 

The combination of Lye from ^Vood- Ashes, or Potash, and Lime 
which has been treated by the Gas generated by Sulphuric 
Acid, Sulphuret of Iron, and Water, for unhairing Hides and 
Shins and for pulling Wool. 

The following process is the invention of Mower, and consists 
in a compound for "liming" and unhairing hides and skins, and 
for pulling wool ; and consists of quicklime, lye from ashes or 
potash, sulphuric acid, and sulphuret of iron. 

A compound is prepared in the following manner : Slack one 
pound of quicklime by the use of four quarts of water in a pail, 
to be as thick as good whitewash. Take a bottle that will hold 
one pint or more, clear white glass being the best. Have a half- 
inch lead pipe twelve to fifteen inches long, and fit one end air- 
tight in the mouth of the bottle. Bend this pipe so that the 
other end will enter the lime in the pail, one or two inches below 
the surface of the lime. Place four ounces of sulphuret of iron 
in the bottle, and cover the same well with water. Add 
sulphuric acid sufficient to cause the contents to boil. Then 
fasten the lead tube in the bottle, and let the other end into the 

1 Maynard's process for bating hides and skins, which can be employed 
in combination witli tliis process or alone is described in Chapter XVII. 



DEPILATORY COMPOUNDS. 279 

lime, as above stated. The sulphuric acid, when in contact 
with water and sulphuret of iron, will generate a gas, which is 
conveyed through the tube to the lime and colors the lime blue. 
The lime being an absorbent, the gas unites with the flour of 
lime. This operation should be performed in the open air, as 
it has a disagreeable odor. "When the action in the bottle 
ceases and the contents become dry, add water and sulphuric 
acid, as at first; but should any water remain in the bottle after 
the action ceases, pour off the water and add water and sulphuric 
acid, as above, and continue the operation until the sulphuret 
of iron is all consumed. The lime is stirred occasionally, so as' 
to mix the gas through the lime. 

In order to test the strength of the thus prepared lime, if 
sufficiently charged with the gas, it will, if a small quantity be 
put on the arm, remove the hair, if any, in five or six minutes, 
causing no pain or doing no harm to the skin. 

One gallon of the above-prepared lime will be sufficient to 
strengthen from five to six gallons of lime prepared after the 
common mode for liming hides. 

The above proportions may be followed for preparing any 
quantity required. 

To prepare large quantities of the prepared lime, for one 
barrel slack thirty-two pounds of quicklime by adding one gal- 
lon of hot water to each pound of lime. 

As there is a difference in the quality of lime, the operator 
will have to use his judgment in preparing it to do the work 
intended. 

Hides in this process of liming should be handled often ; or the 
best way is to have two limes prepared in adjoining vats and 
handle from one vat to the other once an hour for four to six 
hours, and occasionally after, as this process works rapidly, and 
by being handled often, will lime more uniformly. 

For harness, upper, and calf-skins add lye sufficient to give a 
slippery feeling to the lime as follows : For a pack of one 
hundred and fifty sides of upper-leather, harness, or equivalent 
of calf-skins add lye from ashes or potash dissolved in water, 
from ten to fifteen gallons. Eenew the lime by adding of the 
prepared lime from three to six gallons for every new pack to 



280 THE MANUFACTUEE OF LEATHER. 

be limed, -which will keep the lime in good working condition. 
This process, as specified, will lime sole-leather hides in from ten 
to twenty-four hours, harness and upper-leather hides in from 
six to fifteen hours, calf-skins in from three to six hours. All 
depends on the strength of the lime and on being properly 
handled. 

Sole-leather hides, when unhaired, are to be rinsed in cold 
water, when they are ready for the tanning process. Harness 
and upper leather and ski'ns, when unhaired, are to be immersed 
in clear water and worked on the flesh side. When worked 
they are to be put in a vat of clean warm water and allowed to 
remain therein for a short time, and then the grain side worked, 
when they will be ready for the tanning process. 

To pull wool, spread the flesh side up and apply a thin coat- 
ing of the prepared lime with a brush. In about, one hour the 
wool will come oft' easily, after which the skin is immersed in 
water the same as calf-skins and both sides worked, ready for 
the tanning process. 

In the old method of liming the hides become so impregnated 
with lime that much bathing and labor are required to reduce 
them sufficiently to make good leather ; but in this process it is 
claimed that the hides raise rapidly and remain soft without this 
bathing and excessive labor. 

Lime, though an insoluble ingredient, cannot be dispensed 
with, as it is an absorbent, uniting with the gas generated by 
the action of the sulphuric acid, sulphuret of iron, and water. 
Lye, being a soluble alkali, penetrates, cleanses, and softens, in 
connection with lime in removing the hair, and will readily 
wash out with water. Sulphur is very penetrating and soften- 
ing. Iron is important in connection with sulphur in making 
sulphuret of iron and making gas. Sulphuric acid in this pro- 
cess is an important ingredient in preparing hides for tanning 
and in connection with the sulphuret of iron and making gas. 
The above ingredients prepared as specified simply dissolve the 
roots of the hair, and the hide retains its weight and strength. 

This preparation it is claimed is especially adapted for dry 
hides, as the ingredients, except lime, have softening qualities, 
which overpower the lime and raise and plump the hides, so 
that they will be and remain soft and pliable. 



DEPILATORY COMPOUNDS, 281 

By this preparation it is claimed that the cost ot preparing 
hides for tanning is materially reduced, and considerable time 
and labor are saved ; and the tanning process will, if the hides 
have been previously prepared by this process, take one-third 
less time, and will produce leather of better weight, color, and 
quality. 

Depilating and removing Grease with a compound of Water, 
Lime, Soda- Ash, Saltp)etre, and Floivers of Sulphur. 

The ingredients of this compound, and the proportions in 
which they are to be mixed for the purposes indicated, are as 
follows : Pure water, five hundred gallons ; unslacked lime, one 
barrel ; soda-ash, one hundred pounds ; saltpetre twenty pounds ; 
flowers of sulphur, ten pounds. 

The above quantity is for treating one hundred ox-hides (or 
two hundred sides), and the following is the manner in which 
the compound is to be prepared, used, and applied for the pur- 
poses indicated : Clean the hides by water of all salt and im- 
purities, allowing green hides to soak one day and dry hides 
eight days, or thereabout. Then take of pure water, iive 
hundred gallons ; of unslacked lime, one barrel ; of soda-ash, one 
hundred pounds ; of saltpetre twenty pounds, and of flowers 
of sulphur, ten pounds. Mix all of the ingredients well to- 
gether until they are thoroughly dissolved. Then place the 
hides, so cleaned, in the solution and allow them to remain in it 
forty-eight hours. Then remove the hides and unhair them in 
the usual way. 

By the above process it is claimed by Tinnerbolm, the in- 
ventor, that the hair is speedily and thoroughly loosened, and 
the hides, while retaining the portion of their substance which 
can be tanned into leather, are, at the same time, cleaned from 
grease and other substances which prevent them from tanning 
quickly. 

The above procees and solution it is claimed may be used and 
applied in the process and art of tanning or curing all kinds of 
hides and skins, care being taken to regulate the time in which 
they are kept in the solution, according to their thickness and 
the class of skins to be tanned. 



282' THE MANUFACTURE OF LEATHER. 

The composition can be used and applied by any person of 
ordinary skill as a tanner. 

Softening^ Plumping^ and Depilating Hides and Skins through 
the employment of Sulphide of Bariuyn in solution. 

Foley invented the following process for treating hides and 
skins previous to tanning, and it relates to removing the hair 
and epidermis from hides and skins of every description and 
however cured, softening dried and cured hides and skins, 
and separating tlie wool and hair from skins in their natural 
state. 

For unhairing he uses, instead of lime, but in a somewliat 
similar manner, solutions of sulphide of barium of varying 
strengths, prepared by dissolving in water solid sulphide of 
barium, produced by heating finely-ground sulphate of baryta 
mixed with carbonaceous substances to about a white heat in a 
reverberatory furnace or other suitable appliance. 

In treating green slaughter hides and skins to remove the 
hair and epidermis, first wash them to remove the blood and 
dirt, and then immerse them in a strong solution of sulphide of 
barium, about 15° Baume, for about three to six hours. They 
are then withdrawn, again washed, and taken to the beam- 
house, to be treated in the usual manner. 

In the treatment of salted or cured hides and skins for the 
removal of the hair and epidermis, first immerse them about 
ten to twelve hours in an old or partially-spent solution of sul- 
phide of barium, for the purpose of cleansing them and destroy- 
ing the effect of the salt or substance with which they were 
cured ; and afterward immerse them in a solution of sulphide of 
barium of about 6° to 8° Baume for about ten hours, when they 
are ready for the usual treatment in the beam-house. 

In the treatment of dried or flint hides and skins, it is neces- 
sary, before the hair and epidermis can be removed, to soften 
them, and this do by soaking them about twenty-four hours in 
a solution of sulphide of barium that has already been used for 
unhairing, or in a weak fresh solution of about 3° Baume. 

After the dried hides and skins are thoroughly softened in 
all their parts, in the manner above set forth, immerse them, 



DEPILATORY COMPOUNDS. 283 

for the purpose of removing tlie hair and epidermis, in a solu- 
tion of sulphide of barium of about 5° Baume for about six 
hours, and then pass them on to the beam-house. 

In the treatment of skins for the removal of wool and hair, 
apply on the flesh side of the skins, by any suitable means, a 
concentrated solution of sulphide of barium mixed with any 
inert substance to the consistency of a thin paste. The solution 
applied in this manner penetrates the skin, loosens the roots of 
the wool or hair, and allows it to be removed uninjured and in 
its natural condition. 

Tliis invention has advantages over the liming process now 
in use for removing hair from hides and skins and softening 
them, and among others the following are claimed by the inven- 
tor : No part of the gelatinous tissue, grain, or substance of 
the hide is removed or disturbed ; hides and skins are left in 
their natural state and suppleness; at least twenty-five per 
cent, greater weight of leather can be obtained from hides 
treated by this invention than by the old process of liming. 
The hair, it is claimed, is removed in one-twentieth part of the 
time usually employed, thus effecting a great saving in time, 
labor, and expense. Hides aud skins treated by this invention 
and intended for upper-leather do not require to go through the 
operation of "bating," which effects another saving in time and 
expense.^ 

' A number of patents have been obtained for sulpliide or snlphuret of cal- 
cinm for the purpose of depilating hides and skins. Sulphide of calcium has 
been tried by tanners, both in Europe and America, and sometimes abandoned, 
owing to its cost, the increased expenditure for labor attending its application, 
and its supposed injurious action upon tlie hides. It is claimed against 
it that it dissolves and removes a portion of the fibrous tissue, a very formida- 
ble objection to its use, if true. 

In my observations, I have found that sulphur combined with lime simply 
renders the lime more soluble, allowing it (the lime) to act more quickly ; but 
in this state the lime also penetrates the hide, and, notwithstanding repeated 
washings, remains in the hide and forms with the tannin an almost insoluble 
tannate, which deprives the hides of their suppleness and renders them dry 
and brittle. 



284 THE MANUFACTUEE OF LEATHER. 

Depilating luith a comjwund of Watej-^ Burnt Oolite, and 
Muriatic Acid. 

In describing this compound and its use, tlie inventor, Tinner- 
holm, has based it on an estimate of one hundred pounds of 
skins or hides to be treated. 

One-eighth of a bushel of lime is dissolved in water and the 
lime solution poured into a vat containing sufficient water to 
cover the hides. Next a suitable quantity of burnt oolite (or 
other limestone of a like nature — i. e., pure calcareous spar) is 
treated with two ounces of muriatic acid, after which a proper 
quantity of water is added to form a strong lye, when this solu- 
tion is also poured into the vat and the whole is thoroughly 
stirred. The skins or hides are now deposited in the liquor and 
allowed to remain therein three days. They are then taken 
out and the hair scraped off, after which they are placed in a 
vat containing fresh water and left to remain one day. They 
are then removed, the flesh and lime still adhering is scraped 
off, and they are in condition for the bating process, which fol- 
lows the liming in the manufacture of certain classes of leather. 

Depilating with a Mixture of Water, Lime, and Blood. 

The preferred manner of carrying out this plan as stated by 
the inventor Bollman, is as follows : The hides or skins are first 
soaked in water to remove the blood and like adhering matter, 
after which they are drained oft'. They are then placed in a vat 
containing water, lime, and blood in about the proportions of 
one bushel of lime and one and a half gallons of blood to fifteen 
barrels of water for the first supply or charging of the vat. As 
the water, lime, and blood are absorbed, to a greater or less 
extent, it becomes necessary or desirable to replenish them after 
each stock of hides is removed, or, in other words, to maintain 
about the relative proportions stated. 

It will be understood that the proportions of the ingredients 
may be considerably varied ; but the formula given is preferred, 
being found, it is claimed, in practice to give excellent results. 

In some cases the first washing may be dispensed with and 
the skins placed at once in the lime-vat, in which case, the 



DEPILATOEY COMPOUNDS. 285 

skins already containing a considerable quantity of blood, the 
amount separately added to the water of the lime-vat may be 
materially lessened. While as far as it goes the inventor con- 
siders this plan the equivalent of the first, and as included within 
the limits of his invention, he does not deem it the full equiv- 
alent of the first-described method, because he finds by actual 
experience that it does not produce as fine a quality of leather. 
He also claims to have found in practice that hides or skins 
treated in this way require a much less prolonged soaking in 
the tan -bark solution than hides treated in the old way, the 
difference in time being as one and three, and from that to one 
and ten. 

Leather prepared in accordance with this method is soft and 
pliable, yet tough and firm, and, it is claimed, will not become 
rough with use or wear, and will shed or exclude water far more 
perfectly than leather prepared by other plans. Again, he 
claims that he is enabled to accomplish the tanning operation 
with a far less quantity of bark than is required by other plans, 
from one-half to one-quarter the usual quantity being sufficient. 

It is claimed that the presence of the blood causes the hide to 
come from the lime-vat soft and flexible, without being worked, 
handled, or treated in any other way than mentioned. Besides 
decreasing the expense by reducing the required quantity of 
bark and shortening the necessary period of immersion in the 
bark solution, thus permitting other hides to be immersed 
therein, and also saving a great amount of labor formerly 
required in handling the hides in the lime and bark-liquor 
vats. 

A bating mixture has been proposed, in which blood and 
ammonia were to be used (with or without sawdust and urine) 
with water ; and it has been proposed to apply blood " at its 
stage of separation from the serum''^ to skins or hides, and there- 
fore Bollman does not claim broadly the use of blood. The 
invention differs from the first of these plans in that, instead of 
being a bating solution, it is a depilating mixture designed to 
render a bating solution unnecessary, by leaving the hides in a 
soft, pliable, and desirable condition, and, it is claimed, ready to 
be placed in the tan- vat. It differs from the second plan in 



286 THE MANUFACTURE OF LEATHER. 

that, it is claimed, that by the use of lime the depilating action 
is materially hastened, while the presence of blood prevents the 
injurious effects which would otherwise be occasioned by the 
employment of lime. 

Depilating luith Water^ in an open Vessel. 

This invention relates to the employment of a process for un- 
hairing skins of all kinds such as those of sheep, lambs, goats, 
rabbits, hares, calves, oxen, cows, etc., by means of a water- 
stove, in which the skins are vertically suspended. 

The means employed are the following : Make a water-stove 
instead of a fermenting-stove, but with this difference, that in- 
stead of having a hermetically-closed chamber simply establish 
a large or small basin or pan capable of being left uncovered. 
Arrange hooks exactly the same as in a fermenting-stove, and 
hang the skins thereon by the shanks, side by side, taking care 
to keep them perpendicular. The skins being hung up and de- 
scending nearly to the bottom of the basin or pan, fill up the 
latter until all the skins are entirely submerged. The water 
naturally causes the peeling, and when this peeling takes place 
the skin has not suffered at all in the water. On the contrary, 
it has gained in value and the wool is completely preserved. 
When the moment for peeling has arrived, it is only necessary 
to empty the basin or vat, the skins drain separately, and they 
can be peeled easily. By this water system it is claimed by 
Mr. Aime Laure, of Mazamet (Tarn), France, the inventor, that 
he is also enabled, while preserving the leather and the wool, 
to accelerate more or less the operation of peeling. If it is pre- 
ferred to let the skins follow their natural coarse, cold water 
may be used both in winter and summer. It will be under- 
stood that the skins take longer to peel in winter than in sum- 
mer ; but no harm is occasioned by that. If, on the contrary, 
it is desired to accelerate the operation of peeling, use tepid or 
hot water, and add to the bath any material capable of hasten- 
ing this operation — such as soap, soda crystals, strained bran- 
water, etc., — provided, always, that the materials employed are 
not such as would injure either the leather or the wool. 

It may be observed that, if care has been taken to put the 



DEPILATORY COMPOUNDS. 287 

skins into the water-stove perfectly scoured and washed (by 
means of what is known as the " Paech Process," for example), 
wool can be obtained of a value hitherto unknown. 

By this process of peeling, it is claimed by the inventor that 
the leather obtained is not only worth more, but it can be man- 
ipulated immediately, or the skin may be salted, and, more 
especially, it may be dried without losing any of its quality. 

As will have been seen in the foregoing description, the in- 
ventor has tried to replace violent and dangerous means by a 
most natural, practical, and economical method. 

He does not claim laying hides or skins one upon another in 
a bath. This has been done before, and is objectionable, because 
the skins lying one on top of the other prevent free action of 
the bath on their surfaces. In fact, the uppermost skin will be 
finished on its upper surface before any appreciable effect has 
been made on any of the other surfaces, and will mislead the 
attendant into the belief that the lower skins are in the same 
condition as the upper. Again, the pressure of the pile of 
skins is liable to injure the lower skins. Finally, the skins, 
when placed one upon another in a bath, cannot be drained 
without being first rehandled, while by this process, when the 
water is let out, they drain without being disturbed. 

Depilation hy Sulphuret of Calcmvi and Soda. 

Boudet, in trying the old method of depilating by means of 
a paste of orpiment and caustic lime, observed that the arsenic 
had no decided influence upon the hair, and that the depilatory 
action was due to sulphuret of calcium in the nascent state, 
formed by the reaction of lime upon the orpiment (sulphuret of 
arsenic). He replaced the orpiment by sulphuret of calcium, 
which, when made into a paste with lime, acted so promptly 
that, after twenty-four or thirty-six hours' contact, the skins 
were completely depilated. The lime alone has no depilating 
effect, and the sulphuret of sodium only a partial action. 
• Tanners are opposed to this method, which, it is said, sur- 
charges the leather with an amount of water that escapes by 
evaporation during storing, to the great loss of the dealer, but 
we do not think that this objection is tenable. 



288 THE MANUFACTURE OF LEATHEE. 

Potash, Lime, and Orpiment as a Depilatory. 

Macerate the hides for three days, put them in the vat, raise 
three times, and then for each skin put — 

Potash 2| drms. 

Lime . . . . . . . 5 oz. 

Orpiment , J oz. 

This quantity is sufficient for three small goat or sheep-skins. 
For twenty-five hides take — 

Potash 1 lb. 

Lime . . . . . . .2 lbs. 

Orpiment . . . . . . 2 oz. 

The whole is dissolved in fifty gallons of water. 

This vat is much less commended than the preceding, and is 

liable to numerous objections, and the principal is the danger 

to health accompanying its manipulation. 

Depilation hy the Hydrosulphate of Lime. 

Boettger has proposed to depilate all kinds of hides with the 
hydrosulphate of lime, in paste, which is prepared as we shall 
see hereafter. To use it, the skin is put, with the hair up, on 
a table, when the hair is slightly impregnated with the paste, 
so as to penetrate as far as the roots. In the same way is 
treated a second hide, which is placed on the other. These two 
hides are covered with a board loaded with stones. Two 
hours after the hair is transformed into a kind of soap, which is 
easily removed. 

Preparation of the Hydrosulphate of Lime. 

The hydrosulphuret of calcium, or hydrosulphate of lime, 
when it is not convenient to obtain it from gas-works, is pre- 
pared by saturating a very thick milk of lime with sulphuretted 
hydrogen gas. The necessary apparatus is shown on page 289. 

Fig. 78 represents a leaden generator, of cylindrical form, 
thirty-six inches high by twenty-four inches in diameter, sup- 
ported by a wooden jacket. This vessel has a movable cover 
of cast iron, with a projecting ledge, through which pass the 



DEPILATING COMPOUNDS. 
Fig. 78. 





bolts c, c, for fastening it down. In this cover there are three 
openings, as shown in Fig. 79. The larger one, ^y, is the man- 
hole for the admission of the sulphuret 
of iron and for cleaning out. Of the two 
smaller, the one, d. receives the stationary 
funnel tube, d, through which the dilute 
sulphuric acid is to be introduced. The 
side hole, k, contains a short tube, J, with 
a screw at its upper end for coupling the 
flexible exit tube, m (made of vulcanized 
rubber), which is to convey the gene- 
rated gas into the lime paste contained in 

the closely covered receiver, x. A pipe running down the side 
of the generator, interiorly, is for the coupling of the steam 
pipe when the admission of steam is necessary. 

The protosulphuret of iron rests upon the bottom of the 
generator. When'the sulphuric acid and water (one vol. of the 
former to three or four of the latter) are poured in through the 
funnel tube, c?, to the height indicated in the figure, chemical 
action immediately ensues. The water, which is composed of 
oxygen and hydrogen, is decomposed, and the former gas goes 
at once to the iron, which is deserted simultaneously by its 
sulphur, and thus becoming an oxybase indulges its affinity for 
19 



290 -■ THE MANUFACTURE OF LEATHER. 

the sulphuric acid and unites with it to form sulphate of iron. 
The hydrogen unites with the sulphur to form sulphurretted 
hydrogen, which escapes through the tube, 7n, leading into the 
milk lime with which it combines as hydrosulphuret of calcium. 
The current of gas is continued until the lime is saturated. 
When the current of gas slackens, hasten it by the addition of 
a little acid and water. The occasional admission of steam 
facilitates the reaction. When the paste is saturated, stop the 
connection of the tubes 7n and k, and the generator is emptied 
by the man-hole, g, so as to be ready for another operation. 

The receiving vat should be of wood, strongly bound with 
iron hoops, and fitted with a cover and appliances for keeping 
it close enough to confine the gas, but not so tight as to cause 
an explosion. 

The paste should be made in quantities as required, for it 
must be used immediately, as the action of the air soon converts 
it into sulphate of lime. 

Depilation hy Caustic Soda. 

M. F. Boudet, as a substitute for lime, for raising and depi- 
lating hides, proposed caustic soda. For this purpose the liquid 
is prepared by decarbonating a very dilute solution of soda ash 
with a sufficient quantit}^ of lime, allowing repose, and decanting 
the clear supernatant liquor of caustic lye. Hides immersed in 
this liquor swell out rapidly and considerably, and are ready to 
scrape in two or three days. Moreover the alkali forming 
soluble salts with the fatty portions, facilitates the cleansing, 
and produces a smoother grained side than is common. Hides 
thus prepared imbibe the tan liquor more rapidly than those 
which have been treated with lime. They undergo the entire 
process of tanning in much less time, and suffer less loss than 
those prepared by the usual method. Forty- four pounds of sal- 
soda dissolved in one hundred and thirty-two gallons of Avater, 
and mixed with thirty-three pounds of slacked lime, suffice for 
steeping two thousand two hundred pounds of fresh hides. 



depilating by sweating, 291 

Section IIL Depilating by Sweating. 

In the preliminary preparation of sole leather we use the 
"cold-sweat" process, while in Great Britain and other portions 
of Europe, the warm-sweat method is employed ; but for the 
production of upper leather, the hides are limed about as we do. 

Dry flint hides are the ones that are usually prepared in this 
country by the employment of the sweating process for depi- 
lating, and it is highly essential that the hides should be properly 
soaked, and all their parts be thoroughly softened before they 
are subjected to the sweating process, for if not intelligently 
prepared, they harden in spots, forming " old grain." 

" Frieze" is principally caused during the process of sweating 
when the grain of the hide is inclined to be tender and has the 
appearance of being scraped off". " Black spots" or " old grain" 
are blotches of dark color, and when the hide is tanned, rolled 
hard, and finished these spots cannot be buffed off", and some- 
times they extend over the whole side of leather, as has 
been stated in the chapter treating of the washing and soaking 
of hides. 

Gold Stv eating Process. 

This process, much used in New York, New Hampshire, and 
the northern part of Pennsylvania, has all the advantages of the 
older processes. It gives a gain in the leather over the warm 
sweating process and the liming. 

The process is as follows : A vault, pit, or building is pre- 
pared for the reception of the hides. The walls may be built of 
brick, stone, or of a planked frame. There should be one alley 
for entrance six feet long, having a door at each end, the outer 
one made double, and filled in with spent tan, to prevent the 
communication of warm air from without. A ventiduct, made 
of planks ten or twelve inches square, should extend from the 
centre of the bottom three or four rods therefrom, and placed 
not less than four feet below the surface of the ground. This 
serves both as a drain for discharging the water of the vault 
and to admit damp, cold air, to supply the place of that which 



292 THE MANUFACTURE OF LEATHER, 

has become rarefied, and thus keep up a current through the 
ventilator at the top. The ridge of the roof if a vault is used 
maj be level with the ground ; and on the ridge, extending its 
whole length, set up two planks edgewise, two inches apart. 
The space between these is to be left open, but the remainder 
of the roof must be covered with earth, to the depth of at least 
a yard. The earth covering upon the vault and drain is to pre- 
serve a low temperature for the hides so that they may unhair 
without tainting. 

Spring water should be conducted either in pipes or logs, 
around the angles formed by the ceiling with the walls of the 
vault, from which water should be allowed to flow in small 
quantities, either forming a spray, or falling so as to raise a 
mist or vapor, and saturate the atmosphere of the vault. The 
temperature of spring water is generally about 50°. Water 
evaporating at all temperatures, it is plain that if a constant 
supply be afforded, this evaporation, by requiring a large por- 
tion of heat, would keep the temperature of the vault nearly 
uniform. To suspend the hides in the pit, place three bars 
lengthwise, at equal distances, near the ceiling with iron hooks, 
two or three inches apart, inserted therein. Soak the hides as 
usual for breaking, then hang them singly upon the hooks by 
the butt, so that they may be fully spread open. In the course 
of a few days, when the hair begins to loosen upon the upper 
parts, take them down, raise the middle bar, and hang them by 
the other end until they easily unhair. The hides should not 
be broken until they are taken from the vault and are ready to 
unhair. In a good vault where the thermometer ranges from 40 
to 56° F., which it should never exceed, and where there is a 
free circulation of damp air, hides require from 6 to 12 days 
for unhairing. "When the temperature falls below 4-1° F., the 
ventilator should be partially closed, and when it rises above 
56° cold damp air must be forced in, or an increased quantity 
of cold spring water may be thrown from a hose. 

Hides thus treated are free from all extraneous matters, and 
contain all their gelatin, albumen, and fibrin, in an unimpaired 
state. The action is confined to the surface or grain of the 
skin, expanding the outer portion, softening the roots of the 



DEPILATING BY SWEATING. 



293 



hair, and thus rendering its removal easy. The effect is due to 
the softening action of the vapor, and it is a simple case of 
absorption and swelling of the tissues of the skin and roots of 
the hair. 

This process has been proved by experience to obviate many 
of the evils arising from hot sweating or from unhairing the 
hides by the lime process. 

A Building f 07^ Siueating Hides or Skins, 

The arrangement shown in Figs. 80, 81, and 82 for sweating 
hides and skins, is the invention of Mr. William M. Mason, of 



Fis:. 




Buffalo, N. Y., and the valuable points which it contains will 
be readily appreciated by tanners who employ the process of 
sweating. 

Fig. 80 is a sectional elevation of a building embodying the 



294 



THE MANUFACTURE OF LEATHER. 



improvements. Fig. 81 is a horizontal section in line x x. 
Fig. 82 is a vertical section at right angles to Fig. 81. 



Fig. 81. 




Fig. 82. 






* 



W\\\\\\\\\\\\\\\\\\\\\\\\\\\^ 



This invention consists of a vault or apartment having a ven- 
tilator provided with a regulating- valve, and a water-floor con- 
sisting of a series of communicating-troughs, arranged and 
operating as hereafter described, for the purpose of softening 
dry hides and sweating the same. 

In the drawings, A represents a building of any kind, and B 
is a ventihitor at the top. If the whole building is used as the 
vault, the ventilator simply extends from the top, as in black 
lines. Fig, 80, but, if only one story is used, the ventilator is 
extended below and passed through the flooring, as shown by 
the dotted lines, thereby leaving the upper story or stories free 
for other uses. A valve, a. is preferably hung in the ventilator 
at any point, and provided with cords h 7?, by which it is ope- 
rated. The use of the valve is to graduate the escape of the cur- 



DEPILATING BY SWEATING. 295 

rent from tlie interior, by closing more or less of the ventilator 
space. Any desired number of the ventilators may be used, 
and they may be extended to -any desired height, the latter 
being preferable as it produces an active ventilation. A 
water-floor, (7, is employed, to which is applied water to pro- 
duce the evaporation. The inventor prefers the form shown, 
which consists of a series of troughs or water-ways, c c c^ open 
at alternate ends, as shown at d c?, so as to form a zigzag water 
communication around, as indicated by the arrows in Fig. 81. 
The water enters by an induction-pipe, /, at one end, and escapes 
by the eduction-pipe,/', at the other end. This current or flow 
of the water is essential to discharge such gases as are absorbed 
by the water and keep the water pure. Either fresh or salt 
water may be employed ; but the latter is preferable, espe- 
cially in hot weather, as it produces a colder atmosphere, and 
the salt acts as a preservative to the hides in sweating. A diffe- 
rent arrangement of the water-floor and its troughs may be 
used, and the throwing or spraying of the water on the floor 
might be used with a similar effect, g g g are the slats or poles 
for hanging the hides, h h h are slats laid as a flooring over 
the water-troughs, with interstices left between to allow of the 
evaporation. 

By the means above described, there is produced cold sweat- 
ing in contradistinction to the warm sweating heretofore prac- 
tised. By so doing, it is claimed that the requisite dampness 
is always obtained without any danger of heating and spoiling 
the hides. The ammonia and gases are all carried off" as fast as 
they are generated, thus removing at once the great cause of 
putrefaction. There is, consequently, no loss of the hides from 
this source, and but little care or time is necessary in conduct- 
ing the operation, as compared with the usual method. 

Any arrangement of doors, windows, or other apertures or 
entrances may be used, and the vault may be so arranged that 
an opening may be made in the same at the bottom at any time, 
for the purpose of admitting air to assist the ventilating action 
wdien the atmosphere is heavy, as is sometimes the ca.se. 



296 THE MANUFACTUKE OF LEATHER. 

Care to he Observed in Sioeating Hides. 

Some tanners prefer to maintain the temperature for the 
sweating pits at from 60° to 70° F. ; but the risk increases 
largely in proportion to the increase of temperature. 

Faithful attention should be paid to the hides during the 
advanced stage of sweating, and when any give indications of 
advancing too rapidly they should be removed to the bottom of 
the pit, and properly cared for. 

• When the sweating process is used for small hides or kips, 
they should be thoroughly washed in very clean water, spread 
out after four days' soaking, well rinsed and drained, then laid 
together in packs in such a manner that the hair is outward, 
and the pairs of skins back to back. Hang them over the poles 
of the sweating pit, with the tail end upon one side, and the 
head on the other. Then close the door and stop it up well so 
that the air may be excluded as much as possible, and leave 
matters thus until the odor of the sweating process becomes 
quite strong, which is an indication that the process of depi- 
lation is about to begin, and from this time out the greatest 
attention should be paid to the stock. 

The working of the sweating process is shown by a sharp lye- 
which forms under the hair, and which drops oft" the instant 
fermentation sets in. 

Light hides should not be placed in too strong lime ; these 
hides should rather be operated upon by degrees and always 
with weak lime, after coming from the sweating vault. 

The sweating process regulates and hastens the expansion of 
the hide, opens the pores, and places the hide in a state similar 
to that in which it was at the time the animal was slaughtered. 
To prepare it for the leather dressing process, it will be found 
enough to work the hide lightly on the flesh side with the iron, 
when it is taken out of the sweating vat, so as to stretch out 
the wrinkles that may appear before the hide is placed in the 
lime-pit, which, as has been said, should always first contain a 
weakened lime bath. 

With regard to the large hides, such as those imported from 
South America and elsewhere, we urgently recommend that 



DEPILATING BY SWEATING. 297 

tliey should be subjected to the sweating process for, we repeat 
it, the sweating system has not only the effect of facilitating 
the process of depilation, but of giving to dry wild hides that 
development of which they stand in need, 

Buenos Ay res hides are a species of hide which softens easily 
and in a regular manner. It is admitted that hides which are 
allowed to remain continuously in water soften less readily than 
those which are alternately soaked and piled. And now let us 
consider how piling compares with sweating. Piling is nothing 
more nor less than a slow inward sweating, and while it is slow 
you run the risk of having the edges damaged, by giving the 
time necessary to effect a good result. So in order to save the 
back and extremities you are obliged to dispense with a com- 
plete softening of the hide, and moreover lose time, which is 
always the result of irregular soaking. We seek to attain in 
soaking the hide the raising up of the fibres, in order to save 
those parts of the hide which were wet, and became dried dur- 
ing transportation ; and the best mode of doing this consists in 
accelerating the operation, so as to obtain a thorough soaking 
by the sacrifice of from seven to eight days. 

Stagnant water does" not give the dry hide time to become 
completely softened again, at least it injures the grain, which 
becomes lost before the water has had ^me to penetrate the 
fibres of the hide. 

Under these circumstances, sweating is alone of use, and if 
necessary, a softening during twenty-four hours in open water 
will be sufficient to secure a satisfactory result, as experiment has 
proven. 

Soak the hides in water for twenty-four hours, mark the flesh 
side well, and rinse the hair side thoroughly, so as to rid it of 
all foreign substances, so that no faulty spots may ensue ; let 
them drain in a heap during four or five hours, and bring them 
to the sweating process as above described. Sprinkle them 
with fresh water from a gardener's watering-pot, provided with 
a sieve-like spout, and after the hides have been again allowed 
to drain off, put them back in the sweating vat. 

Three sprinklings with the watering-pot will be found ample, 
in combination with the sweating process, to soften the driest 



.298 THE MANUFACTUKE OF LEATHEE. 

and oldest hides to such a degree, that, even if they are of the 
heaviest, they can at once be divested of the hair. Then 
separate them after rinsing them, lay them again in water, clean 
and scrape them, and do not interrupt the gradual course which 
the hide has to undergo. 

What we have last above stated should only be resorted to 
when suitable water is wanting for proper soaking, for we 
recommend above all things that the hide be carefully soaked 
in water, as this raises it well, but in all cases, whichever mode 
of soaking be followed, the hides should never, as a general 
rule, be allowed to stay in the water longer than four days, or 
from five to six days in severely cold weather. Of course the 
sprinkler with a watering-pot is then superfluous, and there 
will then only remain the placing of the hides in the sweating 
vat to be attended to. They should be left in it from four to 
six days, according to the season of the year. 

The Warm Siveating Process. 

The process of warm sweating largely employed in Germany 
and many other portions of Europe is usually conducted in a 
buried box of suitable size, from which the air is rigidly excluded. 
The box has racks firmly attached to the sides, opposite each 
other, and into which stout notched poles are fitted to receive 
the hides after they are properly rolled. The cover of the box 
is usually composed of loose boards, which are convenient for 
handling in filling or emptying the sweat-box. 

After removal from the water and draining off' for a few 
hours, the hides are placed, hairside out, alongside the sweat- 
box, and the sides folded in towards the back, or the hides are 
rolled together from the side towards the back. 

If the sweat-box is of a sufficient depth, folding in of the head 
is not necessary, but otherwise it has to be done to prevent the 
hide from touching the bottom of the box. To keep the head 
from sliding out, which might easily happen, both ends of the 
rolled hide are securely tied with twine. After covering the 
bottom of the box with a layer of spent tan three or four inches 
thick, the. hides are hung close together over the above-men- 
tioned poles. The box is then tightly covered with boards 



DEPILATING BY SWEATING. 299 

upon which, to prevent all access of air, tan is piled to the 
depth of about ten or twelve inches, and well trodden down. 
Warm steam is frequently used in order to accelerate the sweat- 
ing process. Though this method offers some advantages, great 
risk is connected with it and the utmost care must be exercised 
to guard against overheating. Spontaneous heat, which is 
generally developed in five to six days, is always preferable, as 
it acts more uniformly than heat produced by steam. 

After remaining in the sweat-box for a few days, the con- 
dition of the hides is examined by removing the tan from 
one corner and pushing a board far enough back to allow the 
introduction of the hand. If after examining several hides, it 
is found that no heat has been developed and the hair not 
loosened, the box is immediately closed. With some experi- 
ence and skill it is an easy matter to determine how long the 
hides will still have to remain in the box ; fourteen days being 
frequently required before the hair becomes loose. The great- 
est care and precaution are necessary during the entire sweating 
process, as putrefaction promoted by heat makes rapid progress 
and may cause great loss. 

Sweating fresh Hides. 

After cutting out the horns, fresh ox hides intended for sole 
leather ai'e spread out and thoroughly salted upon the flesh 
side. After folding each hide in the middle from head to tail 
and tucking in the hoofs, sides, and head, it is formed into a 
pack. Several of these packs are then piled upon one another 
and covered with Avoolen covers or straw. It is best to perform 
these operations in a cellar. 

It is advisable to use three pounds of salt for a large hide, as 
this quantity is required to protect the flesh side against putre- 
faction, and besides makes the hide more solid. After twelve 
to sixteen hours the hides are turned. The packs are taken 
apart, the hides refolded and again piled up and covered, after 
which they require turning only every three or four days. By 
this method the hair becomes loose in two to three weeks. 

Fresh salted hides are generally not subjected to the sweat- 
ing process, it being preferred to place them, after thorough 



300 THE MANUFACTUEE OF LEATHER. 

soaking in water, in weak lime, when the hair becomes suffi- 
ciently loose in from six to eight days to allow of the hides be- 
ing unhaired. 

Section IV. Other Methods of Depilating now 

NEARLY OBSOLETE. 

The other methods of depilating formerly practised by the 
tanners of Europe at times, were raising by barley and other 
grain dressings, and sour tan-liquor. The first is accomplished 
by placing the hides in a series of vats having a regular gradua- 
tion in the strength, for instance, five hides are placed in the 
first vat where they remain twenty-four or twenty-eight hours, 
and are then transferred to the second, which is slightly more 
sour, and so successively through all the vats. After the skins 
have been treated properly they are washed in clear water for 
the removal of the dirt, and when they come to the last dress- 
ing they are rinsed and scraped over with the fleshing knife; 
at last they are again put in water and brushed over on the 
hair side. 

Some, after this manipulation, lay the hides in the vats, but 
many persons subject them at first to a red dressing. This 
dressing is given by spreading the hides in a vat, one above 
the other, and placing between each pair two or three handfuls 
of ground bark. They add water until the hides are submerged. 
This process requires two days, and the hides require only one 
withdrawal to allow them to drain. 

In giving the finishing wetting, care must be observed to 
supply bark where it is wanted. 

This method of cleaning and unhairing presents as many ob- 
jections as the lime process, and besides has other disadvantages. 
The efficiency of the bath is destroyed when exposed to a low 
temperature, and it is not resorted to when the bath thaws. 
The leather is in danger of being injured by the putrid fermen- 
tation of the materials. 

In England, for coarse hides, they sometimes used the barley 
dressing, and completed the operation in six days. • The hides 
passed through four or five dressings, and from the weak pro- 



OBSOLETE METHODS OF DEPILATING. 301 

gressively to the strong. The hides remained 24 hours in the 
last vat, which was new, and had been soured for 15 days. It 
was made by mixing 60 lbs. of barley meal in hot water. As 
a long time was allowed for the development of acid, and con- 
sequently the dressing was more active than ordinary ones, it 
was necessary to watch carefully when the required point was 
reached, otherwise the hides would be injured. 

Another method was to deprive the hides of hair by stacking 
them in heaps and promoting warmth by covering them with 
straw or manure, until the hair was ready to be removed. If it 
came off" with difficulty upon the beam, its separation was facili- 
tated by the use of sand spread upon the hair side. This 
method is disadvantageous and injurious to the skins. 

liaising hy Sour Tan Liquor. 

This process is still employed to a very moderate extent in 
France and Germany for depilating, and is conducted about as 
follows : — 

The skins are soaked for 24 hours in fresh water, and carefully 
fleshed and deprived of all superfluous parts. ■ When perfectly 
clean and well rinsed, they are deposited in the liquors by which 
they are to be swelled for depilation. These liquors are con- 
tained in a series of eight or ten vats made of oak, hooped with 
iron ; they are 3 feet 8 inches in depth, and 5 feet 5 inches in 
diameter. In each vat deposit seven or eight skins, and cover 
them completely with the liquor. 

Let them soak 24 hours in the first vat, which contains the 
weakest liquor, and during that time take them out twice to 
drain for one hour, the skins being placed on boards which are 
inclined so that the fluid dripping from them runs back into the 
vat. After two days take them out, let them drain one hour, and 
place them in the second vat, which contains a stronger infusion. 
The same operations are repeated daily until the skins have 
passed through all the vats. If at the end of this time the hair 
appears ready to fall ofi', it is removed from the skins b}^ work- 
ing them in the ordinary manner upon the beam with the un- 
hairing knife. In cold weather it is sometimes the case that the 
process has not been sufficiently completed at the end of the time 



302 



THE MANUFACTURE OF LEATHER, 



mentioned, and that the skins require exposure to the strong 
liquors for five or ten days longer, in order that the hair may 
be removed with facility. 

Tlie skins are then " plumped" and treated for the reception 
of the tanning liquor. 

Raising hy Yeast. 

Yeast has the property of raising hides and skins, and has 
heen used for this purpose. It is mixed in a vat with warm 
water, the vat is covered, and fermentation takes place. When 
this is fully established, a quantity of salt is thrown in, and the 
skins are deposited in the vat, the contents of which are then 
treated precisely as in the case of barley dressing. The opera- 
tion can be conducted in the cold, but is much more rapid and 
successful if the temperature of the liquor be kept elevated. 

We have given the above now nearly obsolete processes to 
satisfy manufacturers, rather than to induce them to use them ; 
for the dressings with barley, and generally with grains, are not 
followed now, on account of the influence of the temperature 
upon them, and the great liability of the hides so treated to 
become putrefied, or injured by the undue fermentation of the 
materials employed. 



List of all Patents for Compounds for Depilati/ng^ Hides and Skins, 
issued hy the Government of the United States of America, from 1790 
to 1883 inclusive. 



No. 


Date 






Inventor. 


Eesideuce. 




June 30, 


1836. 


J. 


Banks, 


Dixmont, Me. 


336 


July 31, 


1837. 


B. 


F. Emery, 


Bath, Me. 


2,096 


May 15, 


1841, 


F. 


and H. Robinson, 


Wilmington, Del. 


2,842 


Nov. 4, 


1842. 


J. 


W. Cocliran, 


New York, N, Y. 


12,151 


Jan. 2, 


1851. 


A, 


. H. Ward, Jr. 


Boston, Mass, 


12,369 


Feb. 6, 


1851. 


Z. 


W. Fiske, 


Louisville, Ky. 


17,562 


June 2, 


1857. 


A, 


, K. Eaton, 


New York, N. Y. 


29,392 


July 31, 


1860. 


D. 


Luflvin, 


Cleveland, 0. 


35,293 


May 20, 


1862. 


J. 


Brainard, 


Cleveland, 0. 



' Such patents as No. 144,150 for depilating or removing hair from scalded 
hogs by machinery, and Nos. 121,565 and 141,972 for depilating by pulling 
wool from pelts by machinery, will be found under the list of patents for 
unhairing machines. 



PATENTS FOR DEPILATING. 



303 



No. 


Date. 




Inventor. 


Residence. 


52,464 


Fel). 6, 


1866. 


B. F. Taber, 


Buffalo, N. Y. 


59,627 


Nov. 13, 


1866. 


J. M. MuUer, 


North Becket, Mass. 


78,543 


June 2, 


1868. 


P. Ct. Sclilosser, 


Middletown, Md. 


86,506 


Feb. 2, 


1869. 


L. Clozel, • 


Grenoble, France. 


92,179 


July 6, 


1869. 


A. Fan and E. Fan, 


Castres, France. 


99,387 


Feb. 1, 


1870. 


a. W. Adler, 


Philadelphia, Pa. 


104,734 


June 28, 


1870. 


J. Henrj, 


New York, N. Y. 


116,638 


] 








Reissues 
4,449 


1 July 4, 
1 Sept. 12, 


1871.) 
1871. ) 


J. E. Siebel, 


Chicago, 111. 


4,550 


J 








120,606 


Nov. 7, 


1871. 


R. P. Wilson, 


New York, N. Y. 


123,598 


Feb. 13, 


1872. 


J. Watteau, 


Antwerp, Belgium, 


123,748 


Feb. 13, 


1872. 


C. J. Tinnerliolm, 


Quiucy, 111. 


125,020 


Mar. 26, 


1872. 


A. C. Keith, 


.lersey City, N. J. 


131,927 


Oct. 8, 


1872. 


Wm. Anderson, 


Inverkeithing, G. B. 


136,081 


Feb. 18, 


1873. 


Wm. Maynard, 


Salem, Mass. 


136,082 


Feb. 18, 


1873. 


Wm. Maynard, 


Salem, Mass. 


136,488 


Mar. 4, 


1873. 


J. Carter and A. C. 
Keith, 


Jersey City, N. J. 


145,436 


Jan. 10, 


1871. 


Wm. M. Mason, 


Buffalo, N. Y. 


153,636 


July 28, 


1874. 


C. J. Tinnerliolm, 


Chicago, 111. 


158,608 


Jan. 12, 


1875. 


C. J. Tinnerliolm, 


Keokuk, la. 


158,648 


Jan. 12, 


1875. 


H. Mower, 


Camden, N. J. 


165,348 


July 6, 


1875. 


E. Manasse, 


Napa, Cal. 


176,606 


Apr. 25, 


1876. 


J. L. De Montoison, 


Manchester, Eng. 


181,061 


Aug. 15, 


1876. 


Wm. Farris, 


Yarniouth, Me. 


196,672 


Oct. 30, 


, 1877. 


J. Kent, 


Gloversville, N. Y. 


211,532 


Jan. 21, 


1879. 


C. J. Tinnerliolm, 


Brooklyn, N. Y. 


223,200 


Dec. 30, 


1879. 


J. Wells, 


Wilmington, N. C. 


226,447 


Apr. 13, 


1880. 


J. Foley, 


Montreal, Canada. 


236,860 


Jan. 18, 


1881. 


C. J. Tinnerliolm, 


Brooklyn, N. Y. 


257,442 


May 2, 


1882. 


J. Head, 


Hornellsville, N. Y. 


262,924 


Aug. 22, 


1882. 


J. B. Bollman, 


Dayton, 0. 


281,287 


July 17, 


1883. 


J. L. Moret, 


Pari-s, France. 


285,044 


Sept.18, 


1883. 


A. Laure, 


Mazamet, France. 


287,255 


Oct. 23, 


1883. 


A. H. Stone, 


New York, N. Y. 



304 THE MANUFACTURE OF LEATHER. 



CHAPTEE XVI. 

UXHAIRING AND FLESHING- — UNHAIRING BY THE HAND PROCESS 
— FLESHING BY THE HAND PROCESS — SOAKING HIDES AFTER 
FLESHING — UNHAIRING AND FLESHING BY MACHINERY — tiST 
OF AMERICAN PATENTS FOR UNHAIRING AND FLESHING 
MACHINES. 

Section I. Unhairing by the Hand Process. 

In this country the unhairing and fleshing of hides is accom- 
plished both bj hand and machinery. The hand process is still 
the general manner, and we shall consider it first and the machine 
process afterwards. 

The operations are conducted in the "beam-house," an inte- 
rior view of which showing the forms of beams employed and 
other details is given in Fig, 83 ; the German form of beam and 
stand, used in tawing establishments for skins is shown in Fig. 
84, and the unhairing knife in Fig. 85. 

After loosening the hair, the hides, if they have been sub- 
jected to the sweating process, are removed from the sweating- 
vaults, drawn through fresh water, and allowed to drain. This 
operation prevents drying, promotes cooling off, and interrupts 
putrefaction, and as hides thus treated will usually keep for two 
days without suffering damage, unhairing need not be hurried. 

Limed stock is taken from the "limes" directly to the unhair- 
ing beams and not passed through water as in the case of hides 
that have been subjected to the sweating process. 

The "unhairing" of hides and skins is usually effected by 
placing them upon a beam and scraping the hair off with a con- 
cave blade called the " unhairing knife," which agrees with the 
curvature of the beam, and the operation is performed by men of 
great physical strength, endurance, and skill, acquired only by 
long and continued application ; but this manner is too slow to 







or? 




UNHAIRING AND FLESHING. 



505 



meet the large and constantly increasing demand for leather, 
and consequently aids in rendering this material too dear for a 
commodity of such varied and indispensable employments, and 
in order to facilitate unhairingalarge number of machines have 
been invented both in this country and in Europe. 

Fis. 84. 




Fig. 85. 




To offer increased resistance to the tool in the hand process, 
very fine sand, or road dust, mixed with a small quantity of 
ashes, is sometimes rubbed, into the places where the hair is 
difficult to remove; but this practice is injurious to the grain 
and should not be employed. 

As depilation is more easily accomplished by pushing the 
knife against the hair, the sides from the hind hoof towards the 
head are first operated upon and then towards the back. 

Fresh hides are operated upon as soon as the hair can be 
pulled out around the hoofs, and from the upper part of the 
head. 

After depilation the hides are again placed in water, and 
rinsed and left to remain over night, after which they are 
usually ready for fleshing. 

In the process of unhairing hides and skins sometimes- some 
20 



SOQ THE MANUFACTURE OF LEATHER. 

of them are cut or so injured that thej are reduced from the 
first quality to a lower grade, and thus loss is occasioned. It is 
well known also that after the hair has been removed by the 
usual process of liming and scraping or rubbing it off, there 
remains a short fine hair or fur, and also hair on the edges and 
extremities of the hide, which has to be removed generally 
during the scouring by a sharp knife or other instrument called 
the "short-hair knife." The chief mischief is done to the hides 
in removing the fine hair by cutting or clipping the grain of 
the hide, and when this is too frequently done a guard should 
be attached to the knife in order to prevent the possibility of 
damaging the skin, especially when it is intended for delicate 
work. 

This knife is m.ade of steel, like ordinary knives, with the 
usual handle, but for convenience the blade may be made with 
a double edge, the under side of which is somewhat convex, 
being thickest in the middle and gradually decreasing in thick- 
ness to the edge. The upper side of the blade may have a 
dovetail rib in the middle or thick part of the blade, and from 
this rib to the edge on either side the blade should be somewhat 
concave. 

The guard is made with a dovetail groove, so as to slip closely 
on to the rib. It is made of German-silver, brass, copper, or 
any suitable metal or material, and should project beyond the 
edge of the blade about the sixteenth part of an inch. Its edges 
should be thick enough, or slightly corrugated on the inner 
side, so as to give it requisite stiffness. 

When the knife needs sharpening the guard may be easily 
slipped off and also ground down if necessary. 

The concave side of the blade and the openings of the guard 
allow the hair to pass off without inconvenience. 

The knife is used in the same way as the ordinary knife, and 
is of great value in cleaning kid-skins and other varieties of 
skins used for glove leather, where so much care has to be 
exercised to prevent clipping the grain. 

In France particular attention is paid to the beam work on 
calfskins, and we will describe the process of unhairing and 
fleshing as practised in that country. 



U:^rHAIEIXG AND FLESHIXG-. 307 

The beam-house is so arranged as to avoid loss of time for tlie 
workmen in taking out of the vats and putting back the skins 
they are working. 

They have at least three vats for five or six beam-hands ; 
these vats have a capacity of 375 or 400 gallons each ; the 
water runs into and out of them with rapidity so as to fill and 
empty them promptly. 

The unhairing beams are five feet long, and are covered with 
strong sheet zinc, and thus have a smooth surface convenient for 
the work of the operator, and which avoids breaks and knife 
cuts on the grain side. 

The sheet of zinc is 3 ft. 4 in. long and 2 ft. 1 in. wide; the 
beam presents a convex line of 7|- inches rise. The zinc is 
fastened with round-headed tacks well nailed down, and must 
be put about 1^ inches below the head for the following reasons : 
It often happens that it is necessary to put for dripping 25 or 
30 skins on the same beam and to leave them on it for several 
hours, in which case the undermost hide which rests on the edge 
of the head of the beam will have a deep curved mark pressed 
on the neck, and this mark cannot be taken out in tanning or 
even in currying. The grain at that spot looks like parchment 
and refuses to take the tannin. A prominent French tanner 
tried to discover the origin of these spots, and found that they 
had been caused by the sharp edge of the beam-head, and he 
put the zinc about 1^ inches further down, and from that time 
he did not find any more of these creases which had previousl}'' 
spoiled the skins and diminished their value. 

The beam for fleshing the skins and for thinning the neck is 
broader, and less arched than the other ; it is lens shaped. 
This facilitates the work of the knife, for by having a broader 
surface, the edge is less liable to slip and make flaws, and the 
work progresses more rapidly, as the operator is not forced to 
change the position of his calf-skin so often, and when he reduces 
a throat or a head, he does so in a more uniform manner. 

To unhair slaughtered calf-skins fresh from the Paris market, 
the workman lays two large skins at a time on the beam, and 
when of medium size places three ; but when the calf-skins are 



308 



THE MANUFACTURE OF LEATHER, 



small, places four. In order to avoid scratches and to make the 
action of the knife easier, the workman gives great care to the 
edge, and leaves no trace of hair upon them. He then places 
them in water, and rinses them. 

Next a skilful workman cuts the navels and nipples, trims 
the rumps, fashions the breeches and the tails, going entirely 
around the skins and reaches the neck, which requires special 
treatment. Should there be any flesh left by the butcher on the 
flanks and necks it is lightly removed with the fleshing knifq. 

Section II. Eleshing by the Hand Process. 

This operation, which consists in removing all fleshy and 
fatty matter by means of a sharp blade, requires great skill. In 
some tanneries the work is performed with a fleshing knife hav- 
ing a curved blade, which measures about seventeen and a half 

Fi?. 86, 




inches be^een the handles for the kind used for hides, and 
about si:j^^h and a half inches for skins ; this form of flesher is 
shown in Fig. 86. 

A workman once accustomed to handling this tool can turn 
out very clean work, but it is far better to use for this purpose 

Fig. S7. 



the so-called German fleshino- knife, which has a blade measur- 
ing from tAventy to twenty-three inches between the handles, 
and about an inch and three quarters wide, and which is shown 
in Fig. 87. 

The German, or spring fleshers, are especially recommended 



UNHAIRIN'G AND FLESHING. 309 

for extra clean work, they make a more satisfactory cut than 
the other styles of fleshers, as the workman is able to readily 
adjust it to the curved shape of the beam, which is a great ad- 
vantage over the stiff straight-edged fiesher cutting on an oval 
or convex surface. 

The spring pating fleshers measure about seventeen inches 
between the handles. 

In the commencement of fleshing a hide is laid escutcheon 
part down over the beam, and shaved the entire width of the 
beam and as far down as the workman can reach, this hide 
forming a support which is later on replaced by one entirely 
shaved. The hide to be fleshed next is laid, head down, over 
the beam, and after shaving it, first the entire width of the 
beam and next the sides, it is turned over and finished by 
shaving the escutcheon. In fleshing the left hand precedes the 
right, and, to prevent injury to the hide by cutting into it, the 
workman should accustom himself to drive the knife without 
stopping, as far as he can reach from the top to the bottom of 
the beam. 

The projecting filaments or shreds, and those parts of the 
borders of the skin which are thicker than the rest, are cut off" 
with a sharp knife and the portions thus removed are sold to 
the glue manufacturer. 

For the removal of butcher cuts not accomplished by fleshing 
the smoothing stone often proves a great advantage. 

The saw-toothed flesher sometimes employed for dry hides 
is shown in Fig. 88. 

Fig. 88. 




The turning steels employed are round and three square, 
sometimes the latter style is file cut on one side. The three 
square plain turning steel is shown in Fig. 89. 

In the portion of this chapter devoted to the unhairing of 
calf-skins, page 308, the manner of cutting the navels and 



310 THE MANUFACTURE OF LEATHER. 

nipples, and trimming the rumps, etc., of calf-skins was described. 
Following this operation the flesh sides are gone over with the 
" worker," the skins being pushed crosswise or diagonally, start- 
Fig. 89. 



ing from the humps of the shoulder. Large calf skins are put 
on the beam one at a time ; but two skins are put at once on 
the beam if they are of medium size or thin. 

In order to have this work done successfully the workman 
must, by means of short and brisk blows, applied in a kind of 
moving fashion, get off by main strength all the fleshy and 
parchment-like tissues, from the body of the hide and from the 
sinews of the fore and hind legs. 

The action must be brisk and vigorous on the crupper where 
the nerve of the hide must be entirel}^ broken ; go over lightly 
on the fore and hind flanks without even trying to take oft' the 
tissues with which they are covered ; the collar must also be 
managed carefully; the action must be brisk on the necks and 
heads if there are any tissues. 

In acting in this way the nerves of the hides are completely 
broken on their sinewy parts, and due consideration is given to 
the weak or hollow spots. 

This work is very important, and must be overlooked with 
great care, as the skins that are not worked in the way just 
explained, but which are merely and indiscriminately scraped 
for flesh, never develop themselves well in tanning, refusing to 
absorb the tannin and give poor results in the currying. 

When all the skins have undergone this process they are 
put to soak for six hours in a vat of clear water. 

Then they are next counter-fleshed, putting two hides at once 
on the beam ; they are again soaked in water for an hour or 
two ; they are taken up and gone over with the " worker," put- 
ting two large skins on the beam, or more if they are small ; 
the flesh side to be upwards. It is very important to have this 
operation well done with the " worker," slight blows at first, 



UNHAIRING AND FLESHING. 31T 

then "heavier, in order to empty and purify them of lime ; then 
the grain is cleaned with a knife of which the bevel must be 
very smooth in order to avoid scratches. 

After these two operations the hides are put to soak in clean 
water for three or four hours. They are then taken in hand 
again and given a last working of the grain on the body of the 
hides only ; are rinsed for the last time, and piled awaiting stor- 
age in the vats. 

It requires a sure hand to do the fleshing of a calf-skin. 
The work must be done in mowing fashion only, as straight 
heavy blows are apt to enter the skin and leave marks of cuts. 
The butchers do generally enough mischief to the hides with- 
out the tanners adding any more. It requires then some know- 
ledge and experience to avoid all mishaps; and furthermore 
the tanners' is a rough trade and it requires a pair of stout, 
hard and vigorous arms to make a good beam.-hand. 

Section III. Soaking Hides after Fleshing. 

This operation exerts a great influence upon the quality of 
the leather, and is much more highly esteemed in Germany and 
France than in this country. 

After fleshing, the hides are placed in water as clean and 
clear as possible, and if running water is used a location where 
there is but little current, or none whatever, is chosen. If a 
river or creek has to be used for the purpose, a pole is driven 
perpendicularly in the bottom of the river upon which the 
hides are successively strung through the ear hole and pushed 
towards the bottom, care being observed to keep them spread 
out horizontally. If the water is deep enough as many as 
twenty hides may be suspended one above the other. To give 
a better support to the pole the end projecting above the water 
is pushed through a strap secured to the bank of the river. 

The hides are drawn up twice daily by means of a hook, 
rinsed off, moved and replaced in the manner described. 



312 THE MANUFACTUEE OF LEATHER. 

Soaking Hides in a Steering Cistern after Fleshing. 

In tanneries located on a river or connected with a water 
conduit, provision is generally made in Germany and France for 
steeping cisterns, which are of great advantage for the prepara- 
tion of sole and upper leathers. They are constructed either of 
stone or wood and so arranged that the water can be admitted 
and drawn off very rapidly at will. 

After fleshing the hides are placed in the steeping cistern 
previously filled with fresh water. After 12 hours they are 
moved, the water is drawn off, and the hides, after the admit- 
tance of fresh water, are replaced in the steeping cistern. This 
operation should be scrupulously repeated twice daily to pre- 
vent putrid soaking from making its appearance to the injury 
of the hides. By putrid soaking, which is recognized by a foul 
odor of the water, we understand the assumption of a flabby 
condition by the hides, while, on the other hand, with a fresh 
and sound soaking, they feel firm to the touch and smooth upon 
the grain side, and the water has no odor whatever. 

Hoiv long should the Hides soak after fleshing^ and what indicates 
their readiness for Scouring? 

In this country the hides, after fleshing, are soaked for a much 
shorter period than in Germany and France. Hides intended 
for sole leather, with us, are generally allowed to soak over 
night, while in the countries which have been named, the time 
for soaking is from three to five days, the period depending 
much on the temperature of the water, the hides meanwhile 
being frequently examined as regards their readiness for scour- 
ing. They are ready, 1st, when the fine film still adhering on 
places after fleshing can be readily detached by scraping with 
the finger nail, and 2d, when by pressing with the fingers upon 
the grain side the indented places remain visible. As these in- 
dications can be most readily perceived after rinsing, it is well 
to make the tests after each rinsing operation. 

Hides intended for the production of upper leather after 
being " green shaved" are placed directly in a bate of hen 
manure and worked for 8 or 9 hours with a drench wheel, after 



UNHAIRING AND FLESHING. 313 

which for about 10 minutes they are worked in a wash-wheel, 
and are then worked over with a hide-working machine and 
are next placed in spring water to soak over night. It is con- 
ceded that the bate neutralizes the lime in the hide and leaves 
this class of leather more pliable than when it is subjected to 
long soaking in water, which while it will extract the lime 
imparts an undesirable harshness to upper leather. 

Section IV. Unhairing and Fleshing by Machinery. 

The processes of unhairing and fleshing hides as usually per- 
formed are the most laborious operations in the business of tan- 
ning and require the workman to be constantly in contact with 
cold, wet hides, which is very injurious to the constitution, 
subjecting most operators to disease and forcing many to leave 
the business. Attempts have been made to perform this opera- 
tion by machinery. 

The unhairing of hides and skins by machinery is now an 
accomplished fact, true there is still room for improvement in 
these machines, but in those that are generally accepted by 
the trade these improvements are of only minor importance. 
But such is not the case with fleshing machines and they are 
not generally employed, for in an extended visit to many of 
the largest tanneries in this country I saw but few fleshing 
machines at work. At one tannery located about four miles 
out of Boston, Mass., I saw two fleshing machines in constant 
operation in the beam-house ; but in many other tanneries 
fleshing machines have been tried and abandoned, while in still 
other tanneries experiments were being made to convert them 
into " slating" or other forms of machines. The tendency to 
either " scab" or " slight" the hide is a principal objection to 
fleshing machines as a class, and the necessity of going over the 
edges and other portions of the hide by hand after it leaves the 
machine is another drawback, which deters tanners from em- 
ploying them at present; and still another objection is that 
they work the hides too much in some portions and render 
them soft and flabbv. 



314 



THE MANUFACTURE OF LEATHER, 



Larrahee's Unhairing Machine. 

Larrabee's machine for unhairing and scouring hides and 
skins is shown in Figs. 90 to 95. 




The operation of Larrabee's machine is as follows: The 
machine being set in motion, the operator places a hide or skin 
upon the apron, with the hair side up, spreading it out as 
smooth as he can thereon, the apron in the mean time carrying 



UNHAIEmG AND FLESHING. 



315 



the skin toward the drum D until its end comes in contact 
therewith, when the upward movement of the drum prevents 
the skin from being carried around the inner apron roll, and 
compels the skin to follow the movement of the drum, and 

Fig. 92. 




Fiff. 93. 




pass between it and the feed-roll P, where it is pressed hard 
upon the drum, and, being in a wet state, adheres firmly thereto, 
and is carried around thereby till it is slipped off by coming in 
contact with the shield T. 



316 THE MANUFACTURE OF LEATHER. 

When the skin has advanced around the drum till its end is 
between the drum D and the knife-cylinder J/, the operator 
places his foot upon the treadle, and, depressing it, causes the 
drum D to be moved toward the knife-cylinder till the edges of 
its knives come in contact with the surface of the skin with 
sufficient pressure to remove the hair, the knife-cjlinder re- 
Fig. 94. 




volving at a high rate of speed, while the hide or skin is fed 
forward quite slowly. The skin, continuing to adhere to the 
drum, is carried between it and the brush i?, also revolving at 
a high rate of speed, for the purpose of cleaning the skin. The 
skin then comes in contact with the shield T, and is stripped 
off from the drum, and, sliding down the shield, is discharged 
from its end at any desired point. 

Fig. 90 is a plan of Larrabee's machine. Fig. 91 an end ele- 
vation. Fig. 92 an elevation of the rear side. Fig. 98 is an 
elevation of the end opposite to that shown in Fig. 91. Fig. 94 
is a vertical section on line x x on Figs. 90 and 92. Fig. 95 is 
a section on line z z on Fig. 90, illustrating the method of mov- 
ing the supporting-drum toward the knife cylinder. 

The side frames A A are connected by the tie-rods B B and 
girt G. The work-supporting drum D is covered with rub- 
ber, in order that its outer surface may be elastic and accommo- 




UNHAIEING AND FLESHING. 317 

date itself to any inequalities in the thick- Fig. 95. 

ness of the hide or skin, the boxes a a in 

which this roll is mounted are detached 

and movable in the oblique slots b 5, 

formed in the frames A J., and motion is 

imparted to the drum D by means of the 

driving- shaft ^, and gears F, (7, H and I. 

J and K are two rolls, around which 
passes the endless apron L^ having motion 

imparted thereto by the pulley c on the end of the drum-shaft, 
and the belt c?, leading therefrom to and around the pulley e 
on the end of the shaft of the apron-roll K. 

The upper surface of the apron L\^ placed some two or three 
inches below the level of the top of the drum D^ so that the 
hide or skin will be presented to the drum by the movement of 
the apron at a point where the periphery is moving upward 
and backward, say at an angle of about forty-five degrees, the 
roll t/" being so placed that the apron, passing around it, shall 
move in close proximity to the periphery of the drum i), but 
not in actual contact. 

M is the cleaning cylinder provided with the right and left 
hand spiral projections or blades//, and mounted in the boxes 
g g^ so arranged that the cylinder M may yield and accommo- 
date itself to different thicknesses of hides and skins. 

Eotary motion in the direction of the arrow is imparted to 
the cylinder M by means of the pulley iVon the end of the 
cylinder-shaft, the pulley o on the end of the driving-shaft E^ 
and the endless belt F^^ as shown in Fig. 91. 

P is a feed-roll adapted to be adjusted by means of the set- 
screws m m, rotary motion being imparted to the feed-roll by 
means of the gears / and Q. 

i? is a cylindrical brush, mounted in suitable bearings in the 
frames A A^ in such a position that its periphery shall be in 
contact with the surface of the drum i), or the hide or skin 
passing over and partially around said drum, for the purpose of 
cleaning the hide or skin after it has been acted upon by the 
knife-cylinder M. 

Rotary motion is imparted to the brush i?, in the direction 



818 THE MANUFACTURE OF LEATHER. 

indicated by the arrows, by the belt S, leading from the pulley 
n on the shaft of the cylinder if to the pulley o on the end of 
the brush -shaft, as shown in Fig. 91. 

^ is a curved shield or guard extending across the machine 
below the drum D and the brush jR, with its upper edge in 
close proximity to the under side of the drum, so as to serve 
the purpose of a " doctor-plate" to strip the hide or skin off 
from the drum, and also to direct the hide or skin to the de- 
sired position for discharge. 

?7is a rocker-shaft, having its bearings in the frames J. J., 
and having firmly secured thereon two radial arms, p p, one 
near either end of said shaft, the outer or movable ends of 
which bear against the under sides of the boxes a a, in such a 
manner that a movement of said arms, in the direction indicated 
by the arrow, will cause said boxes a a and the drum i), having 
its bearings therein, to be moved obliquely in an upward direc- 
tion. 

It will be observed that the radius-arms p p and the rocker- 
shaft U are so arranged relative to the boxes a a that the 
radius-arms ppact upon the boxes more in the nature of a 
wedge moving in an arc of a circle than as a direct lifter, and 
that by moving one of said radius-arms around the axis of the 
rocker-shaft slightly, while the other arm j) remains fixed, one 
end of the drum D may be raised or lowered, while the other 
remains stationary, for the purpose of adjusting the drum to the 
proper level. 

T^is another radial arm, also secured firmly upon the rocker- 
shaft Z7, and connected at its outer or movable end by means of 
the connecting-rod V to the treadle W, so that the operator, by 
placing his foot upon the the treadle W, can move the drum 
toward the knife-cylinder. 

Talpey^s Unhairing Machine. 

Talpey's machine for unhairing and scouring hides is shown 
in Figs. 96 to 99. 

The operation of Talpey's machine is as follows : The table 
G is first moved into the position indicated by dotted lines in 
Fig. 96, when the hide or skin to be worked is spread evenly 



UNHAIEING- AND FLESHING. 



319 



thereon with the middle of its length over the slot 5, when the 
table G is moved endAvise in the direction indicated by the 
arrow 7n, by the operator or otherwise, till the stop I strikes the 
bar E and arrests the motion, when the carrier-plate P is made 
to move upward through the slot I) of the table 0^ lifting the 
hide from the table by its middle, and carrying it upward be- 
tween the cylinders H H^, which are made to revolve toward 
each other, as indicated by the arrows n o, and at the same time 
are pressed against the hide by the weights K K, each of which 
acts independently of the others, so that if the hide should be 
thicker at one edge than at the other the cylinders will adjust 
themselves to the general surface of the skin, any small, short, 
or sudden variations in the thickness of the skin being compen- 
sated for by the independent yielding of the several sections or 
any one of them. 

When the hide has passed up between the cylinders it may 
be removed from the plate P, and the cylinders H H^ may be 
thrown apart by the operator pressing downward upon the end 
of the lever iV while the carrier-plate F is returned to the 
starting-point. 

Fiff. 96. 




Fig. 96 is a plan of Talpey's machine. Fig. 97 is a side 
elevation. Fig. 98 is a vertical longitudinal section on line x x 
on Fig. 96, and Fig. 99 is a central longitudinal section through 
one of the knife cylinders and its barings. 

A A are the side frames of the machine, connected by the 



820 



THE MANUFACTURE OF LEATHER. 

Fig. 97. 




Fiff. 98. 




Fig. 99. 




base-board B and the tie rods (7, Z^, ^, and F^ and each having 
formed in its inner face a horizontal groove, a, into which is 



UNHAIRING AND FLESHING-. 321 

fitted the table G^ having in the centre of its length the slot S, 
extending transversely of the table, and of a length equal to the 
width between the frames A A. 

H and H^ are two knife- cylinders, mounted respectively in 
boxes c c and c' c', supported on the screw-pivots d d and d' d' 
set in the slides / / and I' /', which slides are fitted to and 
adapted to be moved horizontally in suitable ways formed in 
the upper portions of the frames A A. 

J J and J' J' are levers, pivoted respectively to the front 
and rear ends of the upper portions of the frames A A Sit points 
marked e e, the short arms of these levers bearing against the 
outer ends of the slides / and /', while the long arms extend 
horizontally and carry thereon the counter-weights K K^ as 
shown in Figs. 96, 97, and 98, which are of sufficient weight, 
and so adjusted that the cylinders H H^ will be forced toward 
each other with enough pressure to produce the desired action 
upon the hide or skin as it is moved up between the cylinders. 

L L are two levers, each 'pivoted, as at/, to one of the frames 
J., with its lower end between the slides /and I\ and so shaped 
and arranged relative thereto that a movement of its top end 
toward the front of the machine will cause the slides /and P, 
and consequently the cylinders H and /?\ to be moved away 
from each other at about an equal rate of speed. 

The upper ends of the levers / / are each connected by a 
link, J/, to an arm or lever, N or N\ formed upon or secured 
to the rock-shaft 0, mounted in bearings formed in the frames 
J., as shown in Fig. 96. 

The arm N is extended beyond the attachment of the link 
i/, to form a lever or handle for operating the levers / to move 
the cylinders outward. 

P is the carrier-plate, arranged in a vertical position, with its 
upper end just below the level of the under side of the table G 
and between the ties or guide-bars E and F^ and set at its lower 
end in the bar Q^ which has a bearing at each end upon the 
vertical guide-rod i?, upon which it is free to be moved up and 
down by any suitable means for imparting a reciprocating 
motion thereto and to the carrier-plate P. 

To each end of the bar Q is attached one end of a cord or 
21 



322 THE MANUFACTURE OF LEATHER. 

chain, >S', which, after passing over the guide-pulley T^ has its 
other end secured to the drum or pulley U^ mounted upon the 
shaft T, adapted to be revolved by means of the crank TT, or 
in any other well-known manner, to wind the cords or chains 
upon the drums, and thus move the carrier-plate upward between 
the cylinders H i?\ to present the surface of the hide or skin 
doubled over the upper edge of the carrier-plate P to the action 
of the knives or scrapers g y' upon the cylinders. 

The cylinders -ff j&^ are made up of several short sections, 
placed end to end upon a shaft, each section being made up'of 
an inner cylinder or sleeve, A, made of metal, and secured firmly 
upon the shaft W in such a manner that it can neither move 
endwise nor revolve thereon, an outer cylinder or sleeve, A', 
made of metal, and provided with the blades ^arranged obliquely 
upon its periphery, and an intermediate cylinder or sleeve, ^, of 
rubber interposed between the two metal sleeves, the rubber 
being so compressed, in uniting the several parts, that the outer 
sleeve of each section is held from rotating about the inner 
sleeve by the friction of the rubber, while at the same time the 
rubber retains sufficient elasticity to allow of the outer sleeve 
yielding radially to accommodate itself to the irregularities in 
the surface of the hide or skin being worked. 

In the under side of the table G is set the staple or pin Z, in 
such a position relative to the slot h that when the table is 
moved under the cylinders H H^ from the front toward the 
rear of the machine the staple or pin I comes in contact with 
the T or guide-bar -fi" just when the slot h in the table is directly 
over the carrier- plate P, as shown in Fig. 98. 

McDonalcV s Uvhairing Machine. 

McDonald's machine for unhairing and scouring hides and 
skins is shown in Figs. 100 to 102. 

■ McDonald's invention has for its object the following de- 
scribed improvement in unhairing and scouring machines, con- 
sisting, first, in the peculiar scouring-roll employed ; second, in 
the arrangement for effecting the release of the skin or hide 
from the feeding-rolls, and from between the scouring and sup- 
porting rolls, when the same may be necessary owing to the 



UNHAIRING AND FLESHING. 



323 



skin or hide becoming folded in its presentation to the feed- 
rolls or to the scouring-rolls ; third, in the organized machine, 
consisting in the combination of the supporting-table, feed-roll, 
bed, scouring and supporting rolls, arranged in relation to each 
other to operate substantially in the manner hereafter described 
in the drawings. 

The operation of the machine is as follows : A hide or skin 
is arranged upon the table by the operator, and presented to 
the feed- rolls D D^^ and by them fed over the bed to the sup- 
porting roll 6^, which is positively actuated and revolved in the 
same direction as the lower feed roll, and the scouring-roll, 
which, preferably, is arranged immediately above the same. 

The relation of the supporting-roll to the scouring-roll is 
regulated by means of the springs supporting its boxes and by 
means of the treadle F. 

It will be observed by thus providing a yielding support or 
bed for the hide to be scoured, or for the skin to be unhaired, 
and by also providing a scouring-roll which shall possess a sur- 
face so shaped as to conform to any irregularity in the surface 
of the hide or skin caused by variations in its thickness, that a 
great improvement has been effected over the stiff arbitrary 
mechanism formerly employed. 



Fig. 100. 



Fig. 101. 




( ^ ^ \ 




A'<^ 



Fig. 100 is a side elevation of McDonald's machine. Fig. 101 
is a central vertical section. Fig. 102- is a plan. 

The scouring-roll A is provided with the system of spiral 



824 



THE MANUFACTURE OF LEATHEK. 



projections or blades a, projecting from the circumference of the 
roll and conversely arranged thereon from the longitudinal cen- 
tre of said circumference. These spiral projections do not ex- 
tend to the edge of the roll, as in the roll in the two previous 
patents by the same inventor, on this machine, but are broken, 
as it were, at certain points, as shown at a'. 




It will be observed that in shaping these projections, and in 
providing the roll with the system of recesses a' on the line of 
the spiral blades or knives, the blades are so arranged that not 
more than two recesses ever come in line ; and it is desirable 
that the recesses and the projections should alternate regularly. 
This scouring-roll is supported upon the frame .5, and is pro- 
vided with the driven cog B\ which is driven by the driving- 
cog G. The driving-cog (7 is fastened to the shaft C\ which 
carries outside the driving-cog G the pulley C^, and upon its 
other end the small driving-cog G^. 

The feed-rolls D D^ are located in front of the table E. The 
upper feed-roll, Z>, is provided with a vertical movement in its 
bearings c/, in which it is floated between the springs. The 
operator may lift the roll by means of the treadle F^ which is 
pivoted at/, and is provided with the arms/\ which are pivoted 
at/^ to the frame of the machine, and which lay hold of the con- 
necting bars /^, which operate the levers /^, pivoted to the side 
of the frame, as shown, and operating, through the links/^, the 



UNHAIRING AND FLESHING-. 325 

boxes carrying the feed-roll i), and, through the link /^, upon 
the other end of the lever, the boxes carrying the supporting- 
roll Q. 

The machine is further provided with the bed H. The boxes 
^, carrying the supporting-roll (?, are supported upon the springs 
(/^, and the degree of tension upon these springs may be ad- 
justed by means of the set-screws (f^ which compress or relieve 
the springs supporting the boxes, as occasion requires, it being 
found in practice that in some instances it is desirable to have 
the boxes yield unequally, so that a hide or skin which is 
thicker at one end than at the other will be firmly held against 
the scouring-roU, while at the same time, by the increased ten- 
sion of the spring, the thin portion of the head or skin is closely 
held against the said roll. 

The feeding-rolls, together with the supporting-roll, are posi- 
tively actuated by means of the gearing //' G' D^ D^. (Not 
shown.) 

The set screws c?^ serve to lift the boxes d^, supporting the 
lower feed-roll, Z^\ when the same may be necessary to secure 
a proper adjustment of that roll in relation to the inner edge of 
the table and to the upper feed-roll. 

McDonald's Ira'prove'ment in Feed- Rolls for Unhairing Machines. 

In feeding skins and hides to unhairing and scouring machines 
it is necessary to spread the hide or skin upon the feed-table or 
belt as flatly as possible, in order that all folds and wrinkles 
may be removed before the same is seized by the feed-rolls. 
It is not always possible, however, to so spread the skin or 
hide, and even if it is properly prepared it is of such irregular 
shape and varying thickness that, unless the feed-rolls act to 
spread as well as feed, it may become wrinkled or folded in its 
passage. As a consequence, the portion wrinkled or folded is 
not only not properly unhaired or scoured, but it is liable to 
interfere with the operation of the unhairing or scouring roll 
upon the remainder, or to be torn or a hole burned therein in 
its passage through the machine. 

To obviate this defect the inventor employs a lower feed-roll, 
which is so shaped that, in connection Avith the upper feed-roll, 



326 



THE MANUFACTURE OF LEATHER. 



it automatically spreads the skin or hide, and at the same time 
requires less care in preparing the skin or hide upon the table 
or belt for feeding. 

Fig. 103 is a perspective of McDonald's improved feed-roll, 
and Fis. 104 is an elevation of the same. A cross section of his 
machine with the feed-roll in place (like the one in Fig. 103) is 
shown in Fig. lOL 

Fis. 103. 




Fig. 104. 




The feed-roll is provided with right and left spiral grooves. 

The right spirals on the one side of the centre act in opposi- 
tion to the left spirals on the other side, and their combined ac- 
tion automatically removes wrinkles and folds, and spreads and 
keeps spread the material presented to them by the opposed 
spreading action of the conversely-arranged grooves. They are 
arranged upon the circumference of the roll, and extend from 
its longitudinal centre to the edge. 

The feed-roll may be used in place of the lower feed-roll of 
the machine patented by McDonald, December 10, 1878, or in 
lieu of the lower feed-roll in the machine patented by him 
February 5, 1878, or instead of the feed-roll i), shown in the 
machine patented by Larrabee, and shown in Figs. 90 to 95, or 
in connection with any other machine, in which it is necessary 
to automatically spread and keep spread the material which is 
being passed between a pair of feed-rolls. 

Of course, this roll may be provided with all the adjustments 
which the rolls above mentioned have in relation to the other 
feed-roll, and in relation to the scouring-roll. 

In operation the hide or skin is seized by the two rolls, and 



UNHAIRING AND FLESHING. 327 

the upper roll pressing it upon the lower roll enables the 
grooves to spread the hide, the portion at the centre first laying 
hold of the hide, and by the continued revolution of the roll 
cause a separating action upon the stock from its centre toward 
each edge as it is being advanced, the folds or wrinkles being 
wiped out by the stretching action of the spiral depressions act- 
ing in opposition to each other from the centre. 

Taylor' s Machine for Unhairing^ Fleshing^ and Working Hides 

and Skins. 

This machine which is for unh airing, fleshing, and working 
hides, calf-skins, pelts, and other skins in the raw or green state 
is shown in Figs. 105 and 106. 

The invention consists in a rotary tool-stock for carrying and 
operating the slickers, stones, blades, or other tools necessary 
to effect the desired treatment of the skin, combined with a 
travelling carriage for holding the skin and presenting every 
portion of its surface to the action of the tools, the skin during 
its treatment overlying a bed, which is preferably supported 
upon springs, so as to yield to any obstructions encountered by 
the tools in working the hides, etc. 

The operation of the machine is as follows : The tools neces- 
sary for the operation to be performed — viz., unhairing, flesh- 
ing, or working the hides, etc. — having been placed in their 
holders, the wheel is rotated by power or otherwise, and the 
hide, skin, or pelt having been placed upon the carriage, its 
near edge is moved over the bed m and there subjected to 
the action of the tools, the skin being progressively moved 
over the bed as each portion is treated until the work is com- 
pleted. 

The rubber face of the bed and its springs, it is claimed, ren- 
der the bed sufficiently resilient to admit of the tools passing 
over any obstruction or extraordinary thickness in the skin 
without damage. 

The tools are set at an angle or tangentially to the wheel's 
rim, in their holders, in order to better perform their necessary 
work. 



328 



THE MANUFACTUEE OF LEATHER. 
Fig. 105. 




Ficr. 106. 




Fig. 105 is a top-plan view, and Fig. 106 a side elevation of 
Taylor's machine, partly in section. 



UNHAIEING AND FLESHING. 329 

In a suitable frame-work, a, there is mounted a shaft, 5, having 
suitable power appliances. Upon this shaft is secured a wheel 
or tool-stock, c, having a number of tool clamps, c?, arranged about 
its rim. 

These clamps consist, in the present instance, of screw-spindles 
e, with squared heads e', seated against rotation in squared holes 
or sockets in bosses / in the rim of the wheel or stock, and 
secured by their tails in lugs (j on the wheel spokes or arms li 
by nuts ^. Bach spindle has its head flattened and extended 
laterally to receive the tool v — viz., slicker, stone, blade, or 
other implement — the tool being held and secured therein by 
suitable clamping devices, as a plate, j/', and bolts or screws, h. 
The tool stock or wheel is provided with any desired or conve- 
nient number of these tool clamps or holders. 

A portion of the frame a' is projected upwardly on the circle 
of the wheel, and the concavity of this projection of the frame 
is covered with a table, I. Within a slot in this table is ar- 
ranged a bed, m, the surface of which is covered with a soft 
material, n — such as rubber cloth, felt, or other fabric- — to break 
the force of the blow of the tools upon the skin being treated, 
and to prevent the breaking of the skin. In order to make this 
bed still more yielding, it is arranged upon springs o, which are 
confined in sockets j? on the frame a', said springs projecting 
out of the open ends of the sockets next adjacent the under side 
of the bed, and bearing thereupon with a tendency to press the 
bed toward the wheel. The bed is held adjustably in place by 
means of screw-bolts r, secured thereto, and passing through 
the sockets and retained by jam-nuts 5, whereby also the posi- 
tion and resilience of the bed may be regulated. 

Upon the top of the projecting frame a', and above the table 
/, are arranged tracks or ways t^ which receive a travelling car- 
riage, w, upon which the skin or pelt to be treated is supported, 
and by which such skin or pelt is moved progressively over 
the bed m, under the operation of the tools on the revolving 
wheel, to treat every part of the said skin or pelt. This car- 
riage may have any suitable fastening devices for retaining a 
skin, and may be further provided with suitable handles or 
other conveniences for moving it upon its ways. 



380 



THE MANUFACTUEE OF LEATHER. 



Janson's Machine for simultaneously Unhairiny and Fleshing 
Hides or Skins. 

This invention relates to improvements in machinery for 
unhairing, fleshing, pairing, shaving, and setting hides, sicins, 
or pelts, by means of which both sides of a hide, skin, or pelt 
may be worked upon simultaneously ; and it consists essentially 
in the use of two knife-cylinders, with their respective elastic 
rollers, instead of a single knife-cylinder as hitherto. The 
inventor claims to attain this object by the mechanism illcis- 
trated in the drawings, in which — 

Figure 107 is a front elevation of the machine; Fig. 108 a 
left-end view of the same ; Fig. 109 a transverse section on the 

Fis.107. 




line 1 2, Fig, 107, showing position of lower roll when inaction; 
and Fig. 110 a plan of the whole as seen from above. 

A A are the end standards. B is the feeding-table ; (7, the 
upper knife-cylinder ; Z>, elastic roll ; E, second or under knife- 
cylinder ; F, lower elastic roll ; 6^, clips or draw-bar ; H^ guide- 
bars for same; /, treadle for raising roll ; K^ connecting-rod; L, 
lever ; i/, cross-shaft ; N^ counter-lever ; 0, bearing for roll Z> ; 
P, counter- weight ; ^, bearing for lower roll, 7^; R, rod for 
actuating same ; S, cross-shaft ; T^ cranks ; f/, hand-lever ; F, 
quadrant ; IF, bell-crank lever ; X, belt for driving shaft ; Y^ 
cross-shaft; Z^ rope-wheels. 



UNHAIRING AND FLESHING. 



331 



It will be seen that, whereas the roll D is capable of a verti- 
cal motion, the lower or second elastic roll, F^ is free to move 



Fig. 108. 



<KH^ 




Fig. 109. 




^/^J^\ 



in a horizontal direction, being hung upon two arms or levers, 
Q Q^ working upon pins secured in the end standards, A A. 
Two rods, R i?, serve to connect ihese arms, Q Q, to two short 
levers, T T, secured upon a cross-shaft, S, arranged immediately 
in front of the machine. Motion is imparted to the shaft S by 
means of a hand-lever, U, working around a quadrant, V, as 
shown. By this arrangement the roll F can readily be drawn 



332 



THE MANUFACTURE OF LEATHER, 



forward, and so brought into action with the lower knife-cylin- 
der, _£/, when required. 

The draw-bar or clip G is connected by a rope passing around 
a guide-pulley secured at outer end of guide-bars H (not shown 



Fig. 110. 




in drawings) with the rope- wheels Z Z^ by which means it is 
caused to travel in an outward direction, carrying with it the 
skin or hide to be operated upon. The skin, hide, or pelt first 
presented between the top knife-cylinder, C, and the elastic 
roller D passes over this latter. It is then caught between the 
roller and the knife-cylinder E. The skin is then drawn out 
by the clips G in the ordinary way, and thus, passing between 
the two sets of cylinders and rollers, is treated simultaneously 
on both oides, the hair and fleshings being separated by a shield, 
over which the fleshings are carried. 

The cylinders are furnished with knives of various kinds, 
according to the requirements of the particular operation to be 
performed upon the skin, and each cylinder will not necessarily 
carry at the same time the same kind of knives, as the two 
cylinders, while working simultaneously, may be performing 
different operations. 

Roherts and Lenox's Fleshing, Slating, and Striking-out Machine. 

The machine for the above named purposes invented by 
Eoberts and Lenox, and improved by Gr. W. Baker, of Wilming- 
ton, Del., is shown in perspective in Fig. 111. 



UNHAIEING AND FLESHING. 
Fig. 111. 



833 




This machine requires but little power to operate it, and, 
when run at a moderate speed of about ninety strokes per min- 
ute, one man can it is claimed flesh or slate about six hundred 
goat-skins per day of ten hours. 



List or all American Patents fok Unhaiking and Fleshing 

Machines. 



List of all 
of the 

No. 



4,570 

20,861 

33,229 ^ 
Reissue > 
2,225 ^ 
49,496 
49,811 
49,839 
56,687 
60,636^ 
Reissue > 
3,839* 



Patents for Unhairing Machines^ issued hy the Government 
United States of America, from 1790 to 1883 inclusive. 



Date. 
July 12, 1812. 
Nov. 4, 1830. 
Oct. 31, 1831. 
May 13, 1834. 
June 13, 1846. 
July 13, 1858 



Sept.lO, 1861. 

Aug. 22, 1865. 
Sept. 5, 1865. 
Sept. 5, 1865, 
July 31, 1866. 



Inventor. 
N. Kirk and S.C.Clark, 
T. Williams, 
T. Williams, 
J. Dunaway, 
G. Welty, 

J. R. Bumgarner and 
L. White, 

H. L. Arnold, 

M. Bray, 

S. S. Weed, 
S. S. Weed, 
A, Adler, 



Dec. 18, 1866. H. Lampert, 



Residence. 
St. Clairsville, 0. 
Rochester, N. Y. 
Rochester, N. Y. 
Woodville, Va. 
West Newton, Pa. 
Davenport, la. 

Elk Horn, Wis. 

Boston, Mass. 
Stoneham, Mass. 
Stoneham, Mass. 
Paris, France. 

Nunda, N. Y. 



334 



THE MANUFACTUEE OF LEATHER. 



No. 


Date. 


Inventor. 


Eesideuce. 


66,124 


June 25 


1867. 


E. Brock, 


Ellenville, N. Y. 


66,176 


June 25 


1867. 


J. Schultz, 


EUenville, N. Y. 


66,640 


July 9 


1867. 


J. SchiflFer, 


New York, N. Y. 


81,247 


Aug. 18 


1868. 


E. Brock and J. Schultz 


Ellenville, N. Y. 


89,864 


May 11 


1869. 


A. Hasbrouch, 


Ithica, N. Y. 


100,907 


Mar. 15 


1870. 


H. Lampert, 


Rochester, N. Y. 


121,565 


Dec. 5 


1871. 


J. Watteau, 


Antwerp, Belgium. 


141,972 


Aug. 19 


1873. 


J. Watteau, 


Antwerp, Belgium. 


144,150 1 

Reissue >■ 

9,714 i 


Oct. 28 
May 17 


1873. ) 

1881. ^ 


D. H. Sherman, 


Jersey City, N. J. 


184,175 


Nov. 7 


1876. 


T. Roberts, 


Lynn, Mass. 


193,412 


July 24 


1877. 


B. F. Larabee, 


Lynn, Mass. 


199,597 


Jan. 22 


1878. 


J. A. Tapley, 


Somerville, Mass. 


200,078 


Feb. 5, 


1878. 


J. W. McDonald, 


Woburn, Mass. 


207,081 


Aug. 13 


1878. 


J. A. Tapley, 


Somerville, Mass. 


209,298 


Oct. 22 


1878. 


G. T. Sheldon, 


Chelmsford, Mass. 


210,797 


Dec. 10 


1878. 


J. W. McDonald, 


Woburn', Mass. 


220,930 


Oct. 28 


1879. 


J. W. McDonald, . 


Woburn, Mass. 


221,545 


Nov. 11 


1879. 


Wm. Gerber, 


Fremont Centre, Mich. 


224,286 


Feb. 10 


1880. 


A. Gerard, 


Soigneies, Belgium. 


227,974 


May 25 


1880. 


Wm. Gerber, 


Fremont Centre, Mich. 


234,542 


Nov. 16 


1880. 


J. Curson, 


Lyons, France. 


239,841 


Apr. 5 


1881. 


A. W. Reid, 


Schenectady, N. Y. 


241,073 


May 3 


1881. 


C. Schultz, 


Milwaukee, Wis. 


241,171 


May 10 


1881. 


E. D. Warren, 


Woburn, Mass. 


249,114 


Nov. 11 


1881. 


C. H. Taylor, 


Woburn, Mass. 


256,326 


Apr. 11 


1882. 


J. M. Jones, 


Wexham, North Wales 


257,495 


May 9 


1882. 


J. W. Janson, 


London, England. 


262,520 


Aug. 8 


1882. 


E. D. Warren, 


Woburn, Mass. 


280,698 


July 3 


1883. 


A. E. Whiting, 


Winchester, Mass. 



List of all Patents for Fleshing^ Machines, issued hy the Government 
of the United States of America, from 1790 to 1883 inclusive. 



No. 


Date 




Inventor. 


Residence 


239 


June 17, 


1837. 


R. Shailer, 


Haddam, Conn. 


4,712 


Aug. 26, 


1864. 


A. Smith, 


Cumberland Valley, Pa. 


59,692 


Nov. 13, 


1866. 


J. S. Wheat, 


South Wheeling, W. Va. 


109,379 


Nov. 22, 


1870. 


J, M. Brown, 


Boston, Mass. 


170,855 


Dec. 7, 


1875. 


Wm. H. Holmes, 


Philadelphia, Pa, 


192,479 


June 26, 


1877. 


T. W. Appleyard and 
W. L. Appleyard, 


Hunslet Carr, England. 



' See also in the list of Unhairing Machine patents, Nos. 4,570, 20,861, 33,229, 
56,687, 66,640, 89,864, 221,545, 224,286, 239,841, 241,073, 249,114, 256,326, 
257,495. 











BATING. 




No. 


Date 






Inventor. 


Residence. 


198,941 


Jan. 8, 


1878. 




E. B. Holcob, and 
D. A. Clay, 


Port Leyden, N. Y. 


212,555 


Feb. 25, 


1879. 




H. A. House, 


Bridgeport, Conn. 


239,522 


Mar. 29, 


1881. 




J. W. McDonald, 


Woburn, Mass. 


247,648 


Sept.27. 


,1881. 




H. A. House and 
S. D. Castle. 


Bridgeport, Conn. 


265,293 


Oct. 3, 


1882. 


} 


A. Whiting, 


Rochester, N. Y. 


275,305 


Apr. 3, 


1883. 







335 



Note.— The illustrations of fleshing knives in this chapter are from the cata- 
logue of Messrs. Wm. H. Horn & Bro., Philadelphia, Pa., who are the leading 
manufacturers in America of tanners' and curriers' tools ; their goods being 
not only largely consumed in this country, but also exported to Russia and 
other portions of Europe as well as to South America. 



CflAPTEE XVII. 

Bating. 

bating and final preparation for the ooze — bating com- 
pounds — list of american patents for bating com- 
POUNDS. 

Section I. Bating and Final Preparation for the Ooze. 

The operation of immersing hides and skins intended for the 
manufacture of upper, Morocco, and other pliable leathers, in an 
alkaline solution consisting of the dung of chickens, pigeons, 
dogs, or in bran water, or in any of the compounds intended 
to supersede the dung solutions, or to be used, in combination 
with them, is termed either "bating," "abating," " grainering," 
" drenching," or " puring." The bate is used in the manufacture 
of soft and pliable leathers after the hides are taken from the 
"limes" and have been " unhaired" and "fleshed," and before 
they enter the " handlers," which is the first stage of the actual 
tanning process. 

The period which the hides or skins remain in the bating 
solution is dependent upon the temperature of tbe bate and the 



336 THE MANUFACTUEE OF LEATHEE. 

thickness of the material subjected to its action. The object of 
bating is to allow the solution to penetrate the hide and neutral- 
ize the lime in the pores. 

The dung of chickens is the material usually employed for 
bating upper leather, while dogs' dung is used for Morocco 
leather, and the bate for sheep-skins is usually prepared from 
bran-water. 

The theory of dung bating, while obscure, is that a chemical 
combination is formed with the lime under the influence of the 
agents of which the droppings are composed, the ammoniacal 
chloride parting with its chlorine to form the chloride of lime, 
which is readily dissolved in water. 

Hydrochloric acid possesses the property of dissolving lime 
in the manner accomplished by the bate, as was shown by Mac- 
Bride in 1774. 

Carbonate of ammonia was employed by Warrington in 1841, 
for accomplishing the purposes of the bate. 

Sugar was used by Trumbull in 1847. in the proportion of 
four or five pounds of cane-sugar or molasses to seventy gallons 
of water, and this solution, it was claimed by him, formed a 
soluble saccharate of lime. 

In addition to the substances narned, carbolic acid, sulphuric 
acid, dilute phosphoric acid, organic acid, muriate of ammonia, 
alum, etc., are now also employed. 

Some of the objections to the present method of bating in 
addition to its expensiveness are : — 

1. The disagreeable odor and uncleanliness attendant upon 
the use of the excrement of animals. 

2. The difficulty in obtaining properly skilled labor to super- 
intend the operation, which is necessary because of the tendency 
to decomposition produced by the use of animal excrements. 
This decomposition is designated by tanners generally as " run- 
ning away," and means literally that the skins are frequently 
decomposed into a state of liquid putridity, and only skilled 
tanners by watching the vats can detect the approach of such a 
condition. 

3. Then there is such great difference in the strength of the 
same kind of animal excrements, as that of dogs for instance (due 



BATING. 337 

to the different varieties of food upon which thej^ have been fed, 
vegetables, bones, etc.), that practically no definite period can 
be positively set within which it is safe to let the excrement 
operate. 

4. The influence 'which the electrical condition of the atmos- 
phere has upon stock in the bate, which is frequently damaged 
or spoiled during thunder-storms. 

The bating is usually accomplished by placing the hides or 
skins in a vat having a circular and tight bottom, over which 
vat is arranged a revolving paddle wheel, marked 1 in Fig. 112, 
which dips into the solution contained in the vat, thereby agitat- 
ing it and maintaining the sides or skins in constant motion, 
thus hastening the work of bating and greatly lessening the 
time and the danger of spoiling the material in the bate. 

After the sides or skins have been properly treated they are 
placed in the interior of the Avheel or drum, marked 2 in Fig. 
112, and washed with clear water for a few minutes. 

The English wheels used for agitating the bate liquor, and 
the wheel used for washing the sides or skins are shown in per- 
spective view in Fig. 112. 

When the sides show the right condition scouring is proceeded 
with, this operation being effected either by hand or by a hide- 
working machine such as is shown in Figs. 114 and 115, or the 
scouring may be performed hy the McDonald, the Larrabee, and 
other machines shown in Section lY., Chapter XYI., at the time 
of unhairing, if such latter operation be performed by machinery. 

The object of this scouring, which should not be confounded 
with the scouring which is to be hereafter described for remov- 
ing the bloom from the hides after tanning, is to free the hides 
from lime and dirt and fit them for the reception of the tannin 
ooze to which they are to be first subjected in the handlers. 

In the preparation of sole leather the hides are scraped on the 
grain side with a curved knife, in order to cleanse them from 
lime remaining in the pores after the last soaking, and this 
operation is termed " graining." 

The hand process of scouring upper leather is effected with a 
tool called a scouring slicker, consisting of a steel blade fixed in 
a stock or handle, the blade being sharpened by grinding it per- 
22 



338 THE MANUFACTUEE OF LEATHER. 

pendicularlj and then on either side, thus producing two edges 
or rather right angles. Tliis tool is shown in Fig. 113. 




Six to ten hides having been spread over a broad beam 'the 
slicker is applied stroke after stroke, but not too vigorously, 
and any fleece hairs which may be found are removed with a 
sharp knife. If during this operation the ground becomes read- 
ily detached so that it runs down perceptibly, the hides have 
acquired a sufficient degree of softness. 

Final Soahing hef ore 'placing the Hides in the Ooze. 

After treating the hides in the above manner, and being as- 
sured by the previously described tests that they have been 
sufficiently soaked, it is only necessary to replace them in water 
for 12 hours longer. The safest indication of the hides being 
ready for the ooze is that, when passing the fingers over them, 
strokes remain as indentations. For the final soaking of sides 
intended for upper leather spring water is usually employed. 

Lampert'' s Appnrattis for Working Hides. 

The machine shown in Figs. 114 and 115 is the invention of 
Lampert, and, in addition to unhairing and fleshing hides, it is 
also much used in working out the lime and dirt after bating. 

Fig. 11"! is a side elevation of Lampert's invention. Fig, 115 
is a transverse section at the dotted line x, Fig, 114, 

The cross-head F and worker g are operated by the pitman 
G and driving- crank H. 

The slides m are arranged in a vertical line upon the side of 
the frame D. and the cross-head moves between them, as shown. 

Lugs cZ, upon the cross-head, embrace the slides and retain 
the former in place, ■ ' 



BATING. 



339 



The worker (/, provided with a knife or scraper, e, is suitably 
secured to the spring bar A, which passes through a slot in the 



Fiff. 114. 




Fig. 115. 



block/, pivoted to the lower end of the suspenders h^ Figs. 11 J: 
and 115, 

These suspenders slide in grooves formed in the lugs c?, upon 
each side of the cross-head, and extend a short 
distance above the latter, where thej are con- 
nected together by the stud o. Fig 115. 

The spring, h\ rests at one end upon the stud 
0, or upon the end of the suspenders, and at the 
other upon a horn, /, projecting from the cross- 
head. 

This spring is retained at a certain degree of 
tension by a staple, a, secured to the cross-head 
and embracing the spring at or near its centre, 
thus causing the worker to bear upon the beam 
(shown in dotted lines in Fig. Hi) or upon the 
hide placed thereon. 

By this arrangement a pressure is obtained not only upon 
the worker independently of the bar h and its adjustments, but 




340 THE MANUFACTURE OF LEATHER. 

also, since tlie elasticity of the former is divided between the 
bar h and spring h\ the worker is retained more squarely upon 
its work. 

The inner end of the bar h is jointed to the link ^, and con- 
nected by it to the pitman G at a, suitable point between the 
cross-head and crank. 

The link i is made adjustable in its length by means of set- 
screws sliding in slots, or by other equivalent device, whereby 
the worker g is adjusted vertically, and consequently the ten- 
sion of the spring bar h varied. 

It will be observed that by the action of the pitman O the 
worker g is lifted from the hide during the forward stroke, and 
depressed upon it during the backward stroke, by means of the 
pivoted spring-bar h and link i, as indicated by dotted lines in 
Fig. 114. A stop upon the stud o, Fig. 115, prevents the sus- 
penders and worker from descending too far. 

A still further vertical adjustment of the worker may be had, 
if necessary, in case of the wearing away of the knife or scraper, 
by inserting the bar h in either of two or more slots formed in 
the block y, Fig. 115. 

In working the flesh side of the hide it is often necessary to 
use a knife or stone, set at such an angle as to cut or separate 
the fibre of the fleshy material. For this purpose the upper 
face of the worker g is somewhat inclined where it is attached 
to the bar A, whereby the tool e acts as a scraper, as shown in 
dotted lines in Fig. 114. 

When, however, the worker is reversed horizontally, as in- 
dicated by dotted lines, the tool assumes a sharper angle with 
the work, and acts as a knife. The worker is secured to the 
bar h in a convenient manner for removal. 

Provision is made for longitudinally adjusting the pivoting 
point of the link ^ upon the pitman, by which the amount of 
lift of the worker and the exact point of its ascent and descent 
is determined. 

The pivoting-point of the bar h to the suspenders h is made 
horizontally adjustable by means of the set-screw t in the block 
y, thus varying the amount of lift of the worker in proportion 



BATING. 341 

to the throw of the crank H^ and also the tension of the springs 
h and h'. 

Hides are easily handled upon this machine, the drum, shown 
in dotted lines, revolves, allowing the hide to move sideways 
with but slight effort, and as the parts are finished the hide is 
drawn towards the operator. 

Section II. Bating Compounds. 

Sating with Muriate of Ammonia either alone or in combination 
with Hen''s^ Pigeon'' s^ or Dogh Diing. 

This bate was patented by Zollickoff'er in 1838, and was used 
very successfully by him for a long period. He used the muriate 
of ammonia as a bate for all kinds of hides and skins, either 
alone or in combination with either hen's, pigeon's, or dog's 
dung, and he states that he bated hides and skins in a much 
shorter time than is required by using either of the last- men- 
tioned substances alone. When he used muriate .of ammonia 
alone, he took seven pounds, which he reduced to a coarse 
powder, and upon which he poured ten gallons of hot water, in 
order to facilitate its solution. This solution he would throw 
into a vat containing a sufficient quantity of clean water to cover 
five hundred pounds of hides or skins, dry weight, in a state of 
preparation for the bate. Into the bate thus prepared the last- 
named quantity of hides or skins was thrown. All kinds of 
skins were bated in one hour, horse hides in two hours, and ox 
hides and other thick hides in three hours. The ox and other 
hides he handled once during their continuance in the bate, in 
one hour after they were placed in it, and when the muriate of 
ammonia was used in combination with either hen's, pigeon's, 
or dog's dung he took two and one-half pounds of muriate of 
ammonia, dissolved in four gallons of hot water, after having 
previously reduced the ammonia to a coarse powder. This 
solution he would throw into a vat containing the qaantity of 
either hen's, pigeon's, or dog's dung bate necessary for bating 
five hundred pounds of hides or skins, dry weight. 

Into this bate was thrown the quantity of hides or skins in 



342 THE MANUFACTURE OF LEATHER. 

the usual state of preparation for undergoing tlie process, taking 
the precaution, however, previously to place them in a pool of 
clear water for five minutes to wash oft* the adhering dirt and 
lime. 

By this last process all kinds of skins were bated in three 
hours, horse-hides in six hours, and ox-hides and other thick 
hides in nine hours. 

The last-mentioned hides Mr. Zollickoffer would handle three 
times, the end of the second, fourth, and sixth hour after they 
were submitted to the bate. 

Horse-hides were handled twice, the end of the second and 
fourth hours ; and all skins were handled once, the end of the 
first hour. 

The hides and skins which were bated by this process were 
reduced and softened analogous to those bated with either hen's, 
pigeon's, or dog's dung alone, and the hairs, dirt, and lime 
worked out with equal ease. 

After they are bated by this process they are to be treated 
like all other hides and skins bated in the usual way. 

In 1842 Zollickoffer patented another composition for bating 
hides by using in combination the muriate of soda, super-tartrate 
of potassa, and tartaric acid. The manner of preparing it is as 
follows: Take two pounds of the muriate of soda, one pound of 
super-tartrate of potassa, and one-half pound of tartaric acid, all 
of which throw together into a suitable vessel and upon which 
pour five gallons of boiling water, and as soon as they are dis- 
solved throw the solution while hot into a clean vat containing 
a sufficient quantity of clear water to cover five hundred pounds 
of hides or skins already unhaired, fleshed, and washed in clean 
water, then agitate the fluid so as to mix the water and the 
dissolved composition thoroughly together, and into this throw 
the prepared hides or skins. 

Skins smaller than calf-skins are removed in less than one- 
half hour and stoned and beamed, calf-skins in one-half hour, 
horse-hides in one hour, and ox-hides in one and one-half hours, 
and placed upon a heap, and after they are stoned returned to 
the bate again, where thev are to remain the same length of 



BATING. 843 

time as before. Upon the completion of the last period the 
hides are to be worked over the beam. 

With this bate hides and skins need not be handled if they 
are put into it in a workmanlike manner ; but before thej go 
into the bark they are to be washed off in clean water, and will 
then be prepared for the action, of the tannin. 

If the hides and skins cannot be conveniently worked out of 
this bate in forty-eight hours they will not sustain the least 
injury, as this process is a preventive of the putrefactive con- 
dition by which hides and skins often become destroyed by the 
bate in common use. 

With this bate it is claimed that hides and skins are reduced 
and softened in a superior manner, and the operator is enabled 
to work out the hair, dirt, and lime with great ease. The grain 
side, gelatine, and general texture not being impaired, and the 
leather prepared after its operation is equally flexible, more 
compact and ponderous than that prepared after the bates in 
common use, which act upon the principle of putrefaction. 

Bating loith a compound of Carbolic Acid, Muriate of Ammonia, 

and Alum. 

Parkins, the inventor of this compound, explains its action 
on hides and skins, which have been depilated by lime, as 
follows: — 

The lime remaining in the hide or skin after all mechanical 
means have been employed (such as repeated washing, rinsing, 
scraping, soaking, etc., for its removal), does not amount to a 
large percentage, still there is sufficient lime left to form with 
the tannin an insoluble compound, which retards the progress of 
tanning by closing the pores and preventing the tan-liquid from 
penetrating the interior of the hides or skins, aside from which 
leather containing this tannate of lime is often harsh and brittle. 

The bating solution which Parkins employs is composed of, 
say three-fourths of a pound of carbolic acid,^ six pounds of 
muriate of ammonia (sal ammoniac), and six pounds of alum 
dissolved in one hundred and fifty gallons of water ; but these 
proportions may be varied to conform to. the experience of those 
who use this compound. 



S44 THE MANUFACTURE OF LEATHER. 

When liides or skins are immersed in this liquid (after being 
freed from the lime by mechanical means) for twenty-four hours 
or longer, it is claimed that all the remaining lime is entirely 
removed, and the pores of the hides or skins opened so as to 
make them absorb the tannin more rapidly and thoroughly, and 
therefore making a plumper and softer leather. 

Hides and skins having been treated with lime should be 
worked in this improved bate precisely as in any other; and as 
regards the length of time they are to remain in the bate, this 
will depend on the thickness and other conditions of the pa'ck ; 
but practical tanners will know when the hides are bated 
sufficiently ; and in order to make the bate penetrate uniformly, 
they are worked on the beam once or twice during the bating. 

Bating ivith a Mixture of Sulphuric Acid with the Lime Liquor 
in which the Shins have been already treated for removing the 
Hair. 

This composition is the invention of Vickers and Holmes, 
and the object is an economical and effective solution for bating 
skins, consisting of a mixture of sulphuric acid with the lime- 
liquor in which the skins have been already treated for remov- 
ing the hair. 

After the skins have been depilated in the usual manner by 
treating the same with lime, the patentees take the resulting lime- 
liquor and dilute it with warm water, and then add sulphuric 
acid until the liquor accords in strength with the character of 
the skins to be acted on. 

This solution is used for bating the skins in place of the usual 
solution of dog and pigeon manure, which, aside from its unclean- 
liness, has a tendency to rot the skins, whereas it is claimed 
that this solution, in which the skins are permitted to remain 
from one to ten hours, breaks up the gristle, opens the pores, 
and loosens the animal matter from the skins, so that it can 
readily be worked out, and at the same time toughens the skins 
and renders them easier to tan and firmer after beino; tanned. 



BATING. 345 

Bating iviih Bran^ Oil of Vitriol^ and Salt. 

Stack lias invented a new and improved process for bating 
and cleansing hides, of which the following is a description. 

In a vat six feet by four feet, and six feet deep, containing 
about three feet of water, put three bushels of bran, three pints 
of oil vitriol, and one peck of salt, and the same proportions for 
vats of different sizes. In this vat put a batch or pack of sixty 
sides or two hundred skins. This bates the hides, it is claimed, 
in from eight to forty-eight hours, according to age — say 
twenty-four hours for calf, goat, and sheep, and forty-eight 
hours for harness and upper leather. When the bate is old, 
eight or nine hours, it is claimed, will do for skins, and twenty- 
four hours for sides, upper, and harness leather; but the time 
will be regulated mainly by the judgment of the tanner. 

For a second pack, one bushel of bran, one pint of vitriol, 
and two quarts of salt will do ; and for a third pack, half a 
bushel of bran, one pint of vitriol, and two quarts of salt will be 
required. 

To prepare the bate, put three bushels of bran in a barrel, 
cover it about three inches with water, and let it stand seven or 
eight days before putting it in the vat. 

For a new bate, always keep a little bran and water in a 
barrel ready for use ; and after the third pailful or two of bran 
and water for every pack, add one pint of vitriol and one pint 
or quart of salt, according as the bate is strong or weak. In a 
new bait, "handle up" the hides three times the first day and 
twice the second. 

In another vat, commonly the one called the pool, with suf- 
ficient water to cover the hides, put in a half- barrel of tar-water 
and soda, in the proportion of two-thirds of a barrel of water, 
one pailful of coal-tar and one pound of bicarbonate of soda, 
and wash and cleanse the hides in it after they have remained a 
sufficient length of time in the bate, which completes the pro- 
cess, and makes the hides ready for the tan-liquors. 

"When the bate gets old, put into it half a barrel of tar-water. 
It acts as a check on it, and keeps the smell down. 



346 THE MANUFACTURE OF LEATHER. 

To make a very fine quality of calf or kip, work the skins 
lightly on a beam out of this mixture in the pool. 

This process it is claimed makes the leather from five to ten 
per cent, heavier than the common process. 

Bating ivith Glucose and dried Sour Cheese. 

The object which McMurtrie had in view in the invention of 
this bate was to form a compound which, when complete, 
would be in condition convenient for packing, storage, and 
transportation, and be always ready for use in any quantity. 
Tliis he claims to have accomplished by thoroughly incorpo- 
rating with dry pulverized glucose, or its equivalent, a suit- 
able proportion, about ten per cent., of dried sour cheese or 
its equivalent, forming a compound which may be packed, 
transported, and stored, without danger of deterioration, and 
which when added to the vats containing the skins impregnated 
with lime, will, it is claimed, undergo molecular transformation 
with production of lactic acid. 

The acid thus formed, combining with the lime, makes a sol- 
uble compound, which may be removed by washing with water, 
or the ordinary treatment of the skins. 

Instead of glucose, starch, dextrine, cane-sugar or other amy- 
laceous or saccharine substances suitable for making a portable 
compound maybe substituted; and for cheese gluten in any 
form, or albumen, from whatever source it may be obtained in 
a dry condition, it is claimed may be used. 

These have, however, the disadvantages of being either more 
costly, and of being more tardy in their action, and glucose 
and cheese are, it is claimed, therefore preferable. In case of 
either of these substances being used, the compound formed 
should be well dried before packing. 

Bating with a Liguor composed of Water impregnated with Sul- 
phur Dioxide that has previously been employed in soaking and 
softening Hides. 

The object of this invention is to cleanse and purify hides 
and skins from lime and humus, and also to remove the epider- 
mis when desirable, and any hairs remaining from the depila- 



BATING. 347 

tion after liming. In practice the inventor, Maynard, discov- 
ered that he could utilize the "soak," which is a liquor composed 
of water impregnated with sulphar dioxide that has previously 
been employed in soaking and softening the skins in preparing 
them for the liming operation. This results, it is claimed, in a 
great saving of expense, and besides avoids the disagreeable 
odor attendant upon the use of excrement of animals, which is 
at present generally emploj^ed. The soak, after the softened 
hides have been removed, contains sulphur, phosphorus, and 
carbon, with traces of nitrogen, in combination with hydrogen, 
because in the soaking operation the skins have absorbed oxy- 
gen while the elements above described have been eliminated 
from the skins and rejnain in the bath. All these in combina- 
tion are efficient, and especially the phosphorus and hydrogen, 
in the cleansing and puring process. It has been found that 
this solution sometimes lacks sufficient ammonia for the purpose 
of cleansing rapidly, and also that the lime requires something 
with which it can enter more rapidly into combination, and 
which will also render it soluble. The inventor, therefore, 
occasionally employs chloride of ammonium, and sometimes 
sugar in small quantities, while he has found argols to assist 
the effect produced by the soak, and to be a very useful, and in 
some cases necessary, adjunct. The inventor claims to have 
found that the use of argols and chloride of ammonium, singly 
or in combination, is non-effective without the soak, inasmuch 
as while the lime has been eliminated the skin itself has not 
been left in that absolutely necessary state of reduction and 
softness technically known to tanners and readily distinguished 
by them as " pured."' This imperfect state or condition of the 
skin Maynard claims to have obviated by the use of the soak, 
either alone or in combination with small quantities of chloride 
of ammonium or argols, or both. 

The inventor claims to have found that in puring he could 
more or less successfully use the following as substitutes for 
the chloride of ammonium and argols, viz: sugar, hydrochloric 
acid, chloride of potassium, and caseine ; but recommends the 
chloride of ammonium and argols as preferable. 

Instead of using the soak, as above set forth, it is, of course, 



348 THE MANUFACTURE OF LEATHER. 

possible to manufacture sulphuretted hydrogen, or even the 
hydrogen compounds of carbon and phosphorus ; but this ex- 
pensive course need not be resorted to, because the soak is al- 
ways at hand and available without cost, after it has served its 
ordinary purpose in the soaking operation. 

By the use of this invention, it is claimed to be practicable to 
calculate, by knowing the strength of the " bate," which is 
easily obtained, the period of time in which the bating or pur- 
ing can be safely and thoroughly performed. This period will, 
in practice, vary somewhat, according to the nature of the skins 
and the electrical condition of the atmosphere ; but ordinarily 
it is claimed that in about one-fifth the usual time necessary 
where animal excrement is employed the paring will be satis- 
factorily completed. Different hides being of varying age and 
toughness are more or less sensitive to the action of lime; there- 
fore a greater or less quantity of lime has to be used, and it 
necessarily follows that the bate also should be of variable 
degrees of strength. Maynard states that he has found in prac- 
tice that the strength of the liquid, when chloride of ammonium 
is used, should vary from one-half pound to one pound per 
hundred gallons of the soak, according to the thickness, age, 
and toughness of the hides and skins to be treated. Although 
this rule is a guide, it is not arbitrary, because much depends 
upon the number of skins to be treated in a given quantity of 
liquid, but these facts or elements being all such as can be 
known by a competent superintendent in advance, it is quite 
easy for him to calculate the short period of time that will be 
required for the bating operation. It is to be understood that 
the liquid should be agitated from time to time and the skins 
moved in the same during this bating process. 

By this invention it is claimed that all the requirements are 
fulfilled at less expense and without the disgusting odor, the 
danger of decomposition by the formation of too much ammo- 
nium, or the action of phosphuretted gases upon the skin, 
attendant upon the use of excrement, while the removal of the 
lime is also claimed to be certain and the action upon the epi- 
dermis perfect, without the possibility of damage.. Further- 
more, the chief agent by which these desirable results are 



BATING. 349 

brought about is a product of the tannery itself, which has 
hitherto been deemed worthless. 

Mullen'' s Process. 

This process consists in drenching in a liquor composed of 
soft soap and sal-soda dissolved in water, in about the following 
proportions: For one hundred sides, about 3 quarts of soft soap 
and one pound of sal-soda, dissolved in a sufficient quantity of 
water to cover the sides. After being properly softened the 
sides are left in the solution four or five days, then unhaired and 
afterwards placed in a fresh solution for twelve hours, after which 
it is claimed they are ready for the tan -liquor. 

Adamson's Process. 

This method consists in bating hides and skins in dilute phos- 
phoric acid, precisely as the ordinary mixtures are used for the 
same purpose. 

Note. — Vast quantities of dilute phosphoric acid are formed in glue factories, 
by treating with muriatic or sulphuric acid and water bones and horn- piths, 
for the conversion of the same into glue-stock. The residuum after this treat- 
ment is dilate phosphoric acid, which is largely permitted to run to waste as 
an article of no commercial value. 

Soderherg^s Process. 

In this process the bate consists of water, chloride of soda, 
and dissolved sulphur, mixed in the following proportions : 
about 400 gallons of water, to which are added about 10 pounds 
of chloride of soda, and 10 pounds of dissolved sulphur, in 
which the hides are treated for about two days. 

The dissolved sulphur is obtained by boiling 10 pounds of 
sulphur, with about 12 gallons of water and about 5 pounds of 
common soda. 

The object of the chloride of soda is to open the pores of the 
hides or skins, so that the sulphur can act upon them more 
quickly for the purpose of removing the lime. 



350 



THE MANUFACTURE OF LEATHER. 



Wilso7i^s Process. 

This process consists in treating hides and skins to a solution, 
for the purpose of bating them after thej have been subjected 
to the action of lime for removing the hair. 

Note. — This bate is composed as follows : Wheat or groand barley, 2 bushels ; 
chloride of sodium or common salt, 50 pounds ; sulphate of magnesia or Epsom 
salts, 3 pounds; sulphuric acid, 3 pounds; the ingredients being thoroughly 
mixed with 5 or 6 barrels of water, or sufficient water to cover when in the 
tank about 150 hides. < 

If the liquor be not agitated the hides or skins remain in the solution about 
36 hours ; but if agitated by a revolving wheel, such as is shown in Fig. 112, 
then it is claimed that about 5 hours will be sufficient for the action of the 
solution. 

JVells^s Process. 

This process consists in bating with a strong solution of salt 
and water. 

Tucker''s Process. 
This bate is compounded as follows : — 



"Water 
Wheat-bran 
Starcli 
Hen manure 
Muriatic acid 
Buttermilk 



20 gallons. 
1 bushel. 
4 pounds. 
1 peck. 
1 pound. 
1 gallon. 



Stir the mixture well before the hides are immersed in it, 
and handle several times daily until freed from lime. 

Swan''s Process. 

This process consists in subjecting limed hides to the action 
of an aqueous solution of alum, whereby it is claimed that the 
lime is removed, by combining with the alum in solution and 
leaving the hide forming an insoluble precipitate that falls to 
the bottom of the vat in which the hides are bated. 



Note. — The alum bath consists of 2 ounces, avoirdupois, of alum to 1 gallon 
of water. 



BATING. 



351 



Turleifs Process. 

This process of bating and tanning hides, consists in first 
subjecting the same to the combined action of carbonic and 
sulplmrous acid gases, and then partially tanning and afterwards 
subjecting the partially tanned hides to the action of said com- 
bined gases, and finally tanning in the usual manner. 



List of all Patents for Compounds for Bating^ 
hy the Government of the United States of 
1883 inclusive. 



Hides and Skins, issued 
America, from 1*190 to 



No. 




Date. 


Inventor. 


Residence. 


592 


Feb. 


3, 1838. 


Wm. ZoUickoflfer, 


Middleburg, Md. 


2,332 


Nov. 


10, 1841. 


S. Guilford, 


Lebanon, Pa. 


2,756 


Aug. 


18, 1842. 


Wm. ZoUickoflfer, 


Middleburg, Md. 


5,261 


Aug. 


, 28, 1847. 


Dr. A. Turnbull, 


London, England. 


8,500 


Nov. 


4, 1851. 


W. B. Milligan, 


Edinburgh, Va. 


35,293 


May 


20, 1862. 


J. Brain ard. 


Cleveland, 0. 


38,267 


Apri 


1 21, 1863. 


R. Wagner, 


Lancaster, Pa. 


59,627 


Nov. 


16, 1866. 


J. M. Mullen, 


North Becket, Mass. 


79,177 


June 


1 23, 1868. 


Wm. Adamson, 


Philadelphia. Pa. 


86,506 


Feb. 


2, 1869. 


L. Clozel, 


Grenoble, France. 


87,202 


Feb. 


23, 1869. 


L. F. Robertson, 


Morrisania, N. Y. 


99,387 


Feb. 


1, 1870. 


G. W. Adler, 


Philadelphia, Pa. 


109,656 


Nov. 


29, 1870. 


C. F. Paukin, 


Charleston, S. C. 


110,161 


Dec. 


13, 1870. 


L. F. Robertson, 


New York, N. Y. 


144,328 


Nov. 


4, 1873. 


M. W. Fry, 


Guyandotte, W. Va. 


146,789 


Jan. 


27, 1874. 


J. Vickers and 
H. Holmes. 


Philadelphia, Pa. 


152,187 


June 


16, 1874. 


Wm. Slack, 


Sussex, Canada. 


153,636 


July 


28, 1874. 


C. J. Tinnerholm, 


Quincy, 111. 


158,608 


Jan. 


12, 1875. 


C. J. Tinnerholm, 


Keokuk, la. 


181,621 


Aug. 


29, 1876. 


A. W. Barnes and 
W. F. Yocum. 


Weston, Mo. 


184,114 


Nov. 


7, 1876. 


M. J. Siiderberg, 


Malmo, Sweden. 


189,536 


Jan. 


2, 1877. 


N. Wilson, 


Becket, Mass. 


194,090 


Aug. 


14, 1877. 


R. Hein, 


St. Mary's, Pa. 


197,739 


Dec. 


4, 1877. 


Wm. McMurtrie, 


Oxford Township, Warren 
Co., N. Y. 


223,200 


Dec. 


30, 1879. 


I. Wells, 


Wilmington, N. C. 


229,928 


July 


30, 1880. 


T. P. Tucker, 


Independence Co., Ark. 


237,630 


Feb. 


8, 1881. 


J. S. Swan, 


Mongaup Valley, N. Y. 


249,540 


Nov. 


15, 3 881. 


Wm. Maynard, 


New York, N. Y. 


262,516 


Aug. 


8, 1882. 


M. Turley, 


Council Bluffs, la. 



' See also patents, Nos. 76,824, 104,719, 135,214, 196,672, 221,187,. 254,962, 
and 262,924 in Tanning Processes, etc. 



PART V. 

CHAPTEE XYIII. 

HANDLING- AND PLUMPING. 

Section I. Handling. 

The occasional removal of hides or sides from the vat, and 
then replacing them, also the agitation of the stock at stated 
times while remaining in the liqaor in the vat, is termed "hand- 
ling," the object of which is to equalize the action of the lime 
in the unhairing process, the bate in the bating process, and of 
the weak liquor or ooze in the first stage of tanning. 

The old manner of handling hides like most of the primitive 
methods of the tanner's art was exceedingly slow as well as 
laborious ; but of late years numerous appliances have been per- 
fected for mechanically performing this work by means of which 
the stock is handled with great facility and at the expenditure 
of but little labor. One .old method was to haul up the sides by 
hand from the vat and pile them, and in this condition, allow 
them to press and drain, and then after a sufficient time throw 
them again into the vat. 

Another and later method was to " shift" or change the sides 
from one vat, over into another by means of hooks. 

Handling and transferring the sides by the medium of a 
revolving device, such as the hand reel, is an old-fashioned method 
which has not yet become obsolete ; but which continues to be 
employed in the majority of both small and large tanneries in 
this country. 

This manner of handling seems to be both convenient and 
economical, and as there are but few objections that can be 
urged against it, there are at present but slight chances of it 
being generally abandoned for later processes, of which we have 
a great variety. 



HANDLING AND PLUMPING. 353 

There are two modes in vogue of connecting the sides, which 
are to be handled, with the reel. One is to tie them together 
with strings and the other is to connect them with a tie-loop ; 
but the first method is most commonly employed, and is the 
least expensive. 

The hand-reel is about three feet high and is made as light as 
possible, consistent with requisite strength, in order that it may 
be readily moved by two men from one vat to another. 

When in use the reel is placed intermediately on the alleys 
between the two vats in which the hides are to be handled and the 
sidesor hides are drawn over thedrumby the workman who turns 
the crank attached to the shaft on which the drum is fastened. 
Two men are required to operate this reel, one to adjust the 
sides or hides in the head vat, and the other to work the crank. 

Another form of handler in use is known as the rocker 
handler, and it consists of a frame constructed of wood, and 
hung by pivots in the centre of the top of the vat so as to give 
a dipping movement of 7 or 8 in. to each end of the frame, and 
the sides are hung over sticks placed across the frame from the 
two sides, motion being usually imparted to the handler from 
shafting placed overhead. 

The apparatus shown in Figs. 116 and 117 was invented by 
L. 0. England, in 1871, and consists in a good method of keep- 
ing the stock suspended in the liquor so that all parts may be 
brought into constant contact with the ooze, and its employment 
in liming, bating, and handling should produce a smooth grain 
and good quality of leather. 

Fig. 116 is a perspective view of the apparatus, showing it 
removed from the vat. Fig. 117 is a vertical section of the 
same showing it applied to a tan-vat. 

The frame i^is made to conform to the interior of the vat, 
and consists of the upper and lower rails, jS^ /S'\ S^, and S^, and 
the cross rails -£/, HJ^, E,^ and ^^, which are joined together by 
means of the uprights U, Z7^, U^, C^, and U*, and which uprights 
serve as guides to retain the frame in a horizontal position. 

The frame i^is also provided near the lower part with two 
diagonal braces, J5, B^, at the point of intersection of which is 
23 



354 



THE MANUFACTURE OF LEATHER. 



an upright shaft, i?, to which power is applied to operate the 
frame, the braces serving to agitate the liquors. 

The series of bars d d d, are held bj the binders 1\ T^ which 
prevent them from shifting as the frame moves downward. 



Fi-. 116. 




Fig. 117. 




The stock is hung on the movable bars d d d with head and 
butt down, and the proper liquors supplied. 



HANDLING- AND PLUMPING. 355 

The frame is placed in the vat so that the top of the stock 
resting on the bars may be about eight or ten inches, more or 
less, below the surface of the liquors. 

The whole frame is then caused to move upward in a vertical 
line of a few inches, four to six being sufficient, but should not 
be allowed to raise the stock above the surface of the liquor. 
The stock being loose on the bars will, when the frame moves 
downward, be left suspended in the liquor, entirely free from 
contact with the bars, thus allowing the liquor free access to 
the parts of the stock, which, when the frame is at rest, adheres 
to the bars on which it is placed. I'lie upward and downward 
vertical motion given to the frame will keep the stock at nearly 
the highest point at which it is raised by the first stroke of the 
frame upward, the frame being moved faster than the stock 
would sink in the liquor if unobstructed. Every returning 
upward stroke of the frame will carry the stock back to the 
highest point again. The frame is caused to move only so fast 
as will -have the desired effect, and at intervals, as occasions may 
suggest. 

The specific gravity of the frame and stock being very small, 
the power required to give the necessary motion while they are 
submerged in the liquor is correspondingly small. 

The paddle-wheels for handling shown in Chapter XVIL, Fig. 
112, which were also invented by L. C. England, in 1847, are 
largely employed in handling heavy, medium, and light leathers. 

These wheels work within three-quarters of an inch of the 
sides and are usually five and a half feet in diameter, and have 
eleven paddles about seven-eighths of an inch thick, and spaced 
equidistant apart, which is about eighteen inches between 
centres at the outer edge. 

The vats in which the wheels revolve have the bottom con- 
cave to conform to the convexity of the wheels which are placed 
over the centre of the vats, so that the wheels dip about eight 
inches in the liquor, and thereby cause a gentle but thorough 
agitation of the ooze and stock, which moves in an opposite 
direction from that of the wheels. 

The motion of the wheels causes the stock to move up in front, 
pass under the wheels, and down on the concave bottom to the 



356 THE MANUFACTURE OF LEATHER. 

back of the vat, and thus by means of the paddles, and the con- 
stant changing position of the stock a thorough and gentle 
agitation is maintained. But if the bottom of the vat should be 
made square, the agitation would be too great to answer the 
purpose. 

No fixed length of time can be set for running these wheels, 
as the period depends upon the stock being handled ; light sides, 
as those used for upper leather, being handled for a shorter 
period and not so often as the heavy whole hides employed for 
making enamelled and patent leathers. 

The wheel for no class of leather should be run at a greater 
speed than eighteen revolutions to the minute, and the motion 
should be steady and regular. Cog-gearing is best, and pos- 
sesses a great advantage over belting, as the latter, from the 
slow motion required, often becomes troublesome. 

Wheels of this kind'are generally arranged in a line, as shown 
in F.g. 112, and sometimes so constructed that any one of them 
can be thrown out of gear, by means of a clutch connected with 
the loose pinion on the shaft. 

It has at times been tried to apply these wheels to quicken 
the after-process of tanning ; but while they answer for light 
leathers, it is the opinion of some who have experimented with 
them upon heavy leathers that they will not answer ; but not- 
withstanding this opinion, I have seen them successfully em- 
ployed at Newark, N. J., and other places, for tanning heavy 
whole hides to be used in the manufacture of enamelled leather. 

This wheel furnishes a most simple and effectual mode of 
moving the incipient leather in the liquor, and does away en- 
tirely with the necessity of handling by hand, facilitates the 
after-process of tanning, economizes in labor, forms a handsome 
grain, and in all respects improves the quality and texture of 
the leather. 

Methods of handling, such as lacing it together and drawing 
the stock through rollers, or placing the hides, sides, or skins 
upon a web, unlaced and feeding the stock to the rollers, are 
not now employed in this country. However, they continue to 
be profitably used for some classes of leathers by a few European 
tanners, the theory being that by pressing the liquor out of the 



HANDLING AMD PLUMPING. 357 

pores in handling that, upon re- immersion, the liquor into which 
the stock is placed acts more quickly and in the end produces a 
heavier weight than is ordinarily obtained. 

In the manufacture of pebble and grain leathers the sides are 
tacked upon sticks and handled into stronger liquor about every 
three days, and it might here be stated that any method of 
handling which allows both the grain and flesh sides to be uni- 
forml}^ exposed to the action of the liquor will fill all the re- 
quirements, provided there is a gentle agitation of the fibre at 
occasional periods. 

In some portions of the country the handling is performed by 
placing the stock in the interior of a large revolving drum 
about 10 feet in diameter, one half of which turns in the liquor 
of the vat, the centre shaft upon which the drum is supported 
turning in bearings resting upon the top of the vat. 

The interiors of these drums are best divided into three or four 
compartments, as it is easier upon the green stock than allowing 
it to be treated in an unpartitioned wheel, and besides the 
operation of the contrivance is facilitated by retaining a portion 
of the contents near the centre. 

In Gorsline's apparatus for handling, the sides or skins are 
placed in the vat resting upon five straps, having cross slats at- 
tached to them, and one end of each of the straps is attached 
to the top of the vat, and when it is desired to raise the pack, the 
centre strap is wound around a drum which gradually raises it, 
and as it approaches the top the operator standing upon the 
alley can easily seize the hides and throw them out. 

The slats slide over the centre strap which winds upon the 
drum, thus preventing them from striking the frame and stop- 
ping the machine. 

In raising the pack the inclined position it assumes has a 
tendency to wash off the sediment or bloom, presenting the same 
advantage in this respect as in handling by hook in the ordinary 
way. 

This contrivance is better adapted for handling kips and 
skins than for heavy sides or hides. 

Steinmann's apparatus for handling hides in the lime-pits is 
shown in Figs. 74 to 77. Study's contrivance for liming hides 
has been described on page 269. 



358 



THE MANUFACTURE OF LEATHER. 



List of all Patents for Tanners^ Vats, Agitators, and Handling Appli- 
ances, issued by the Government of the United States of America, 
from 1790 to 1883 inclusive. 



No. 


Date 




Inventor. 


Residence. 




Jan. 9, 


1834. 


S. Stem and D. 
Wireman. 


Mechanicstown, Md 


795 


June 20, 


1838. 


W. L. J. C. Rouse 
and S. Tabor. 


Wade's Post Office, 


1,906 


Dec. 17, 


1840. 


W. Buchannan, 


Milford, Pa. 


2,552 


April 11, 


1842. 


J. Southvvick, 


Boston, Mass. 


2,729 


July 20, 


1842. 


W. Wallace and 
J. Fleming. 


Lehman, Pa. 


2,868 


Dec. 5, 


1842. 


D. H. Mason, 


Dahlonega, Ga. 


4,851 


Nov. 14, 


1846. 


A. H. Brescliermann, 


New York, N. Y. 


6,340 


April 17, 


1849. 


T. W. Brown, 


Howardsville, Va. 


7,854 


Dec. 24, 


1850. 


L. C. England, 


Williamsburgh, N. 


8,500 


Nov. 4, 


1851. 


W. B. Milligan, 


Edinburgh, Va. 


12,369 


Feb. 6, 


1855. 


L. W. Fiske, 


Louisville, Ky. 


14,135 


Jan. 22, 


1856. 


D. H. Kennedy, 


Reading, Pa. 


15,844 


Oct. 7, 


1856. 


E. A. Eliason, 


Georgetown, D. C. 


20,093 


April 27, 


1858. 


D. Philbrick, 


Manchester, N. H. 


23,053 


Feb. 22, 


1859. 


C. Weston, 


Salem, Mass. 


33,203 


Sept. 3, 


1861. 


W. P. Martin, 


Salem, Mass. 


33,448 


Oct. 8, 


1861. 


S. J. Patterson, 


Bridgeport, Conn. 


33,645 


Nov. 5, 


1861, 


D. A. Havaland and 
S. A. Phillips, 


Fort Dodge, lud. 


39,824 


Sept. 8, 


1863. 


B. B. Mereness, 


Georgetown, N. Y. 


41,336 


Jan. 19, 


1864. 


J. S. Wheat, 
/ W. H. Study, S. J. ■ 


Berkley Springs, Va 


48,758 


July 4, 


1865. 


} Miller and A. B. 
( Barnett. '. 


- Economy, Ind. 


59,469 


Nov. 6, 


1866. 


J. Snell, Jr., 


Pottsville, Pa. 


68,861 


Sept. 17, 


1867. 


L. C. England, 


Philadelphia, Pa. 


70,306 


Oct. 29, 


1867. 


J. C. Williams, 


Philadelphia, Pa. 


80,947 


Aug. 11, 


1868. 


J. Hammond, 


Lattsburgh, Ohio. 


91,402 


June 15, 


1869. 


H. W. Adams, 
^ T. K. Parsons, Chas. • 


Philadelphia, Pa. 

1 


116,626 


July 4, 


1871. 


\ E. Getchel, and S. 
i W. Fairfield. 


- Salem, Mass. 


116,766 


July 4, 


1871. 


N. Smith, 


McAllisterville, Pa. 


122,157 


Dec. 26, 


1871. 


J. W. Coburn, 


East Walpole, Mass 


123,192 


Jan. 30, 


1872. 


D. F. Noyes, 


Lewiston, Me. 


135,231 


•Jan. 28, 


1873. " 






Reissue 






C. H. Manning, 


Washington, D. C. 


8,639 


Mar. 15, 


1879. 






138,906 


May 13, 


1873.. 




^ 



HANDLING AND PLUMPING. 



359 



No. 


Date. 




Inventor. 


Residence. 


150,657 


May 5, 


1874. 


S. H. Hall, 


Belle Plaine, Iowa. 


163,021 


May 11, 


1875. 


C. H. Manning, 


Washington, D. C. 


165,212 


July 6, 


1875. 


W. Coupe, 


South Attleborough, Mass. 


170,330 


Nov. 23, 


1875. "i 






Reissue 




[ 


0. W. Bean, 


Tecumseli, Mich. 


7,311 


Sept. 19, 


1876.^ 






182,198 


Sept. 12, 


1876. 


J. J. Johnston, 


Columbiana, 0. 


182,614 


Sept. 26, 


1876. 


J. R. Teass, 


St. Albans, W. Va. 


3 97,426 


Nov. 20, 


1877. 


C. Steinmann and 
J. Mitzger. 


Cincinnati, 0. 


199,534 


Jan. 22, 


1878. 


J. T. Gorsline, 


Parma, N. Y. 


205,596 


July. 2, 


1878. 


A. Whiting and 
J. A. Smith. 


Rochester, N. Y. 


211,063 


Dec. 17, 


1878. 


C. Steinmann, 


Cincinnati, 0. 


214,220 


April 8, 


1879. 


A. Whiting, 


Rochester, N. Y. 


214,439 


April 15, 


1879. 


A. Palmer, 


Rochester, N. Y. 


219,537 


Sept. 9, 


1879. 


J. A. Smith, 


Rochester, N. Y. 


240,988 


May 3, 


1881. 


C. Flohr, 


Canisteo, N. Y. 


276,634 


May 1, 


1883. 


G. Ruemelin, 


Milwaukee, Wis. 


278,331 


May 29, 


1883. 


D. Halsey, Jr. 


Newark, N. J. 


281,061 


July 10, 


, 1883. 


J. Head, 


Richmond, Va. 



Section II. Swelling or Plumping. 



The swelling or "plumping" follows the unhairing and fleshing, 
and after the bating of the hides, which has been described, and 
it consists of a more or less prolonged immersion in an acid liquor 
which is gradually increased in strength. Its essential action 
consists in completing the swelling of the cells, distending the 
pores, and thus favoring the absorption of the tannin. A sec- 
ondary action takes place ; it is a commencement of tanning due 
to the presence of a certain quantity of tannin in the liquor ; 
the swelling being due to the action of the acetic acid and of 
the lactic acid of the hide. Both acids are products of decom- 
position and oxidation of the tannin. 

Some wood vinegar may be added to the sour tan liquor in 
order to accelerate the swelliag. This process does not cause 
any damage to the quality of the leather ; but some tanners 
replace the acetic acid by sulphuric acid, which, at an equal 
degree of acidity, costs considerably less. This practice is 
prejudicial to the quality of the leather. It is true that the 



860 THE MANUFACTURE OF LEATHER. 

swelling is satisfactorily produced, and the leather looks well , 
bat, prepared in this manner, it retains traces of sulphuric acid 
which corrode it internally after a time, and make it very 
brittle and more subject to alteration by moisture, and there are 
other defects which will be mentioned shortly. 

The " plumping" process is applied to the heavier classes of 
hides only, such as those employed for the manufacture of sole- 
leather, upper-leather, etc. 

Pluinping hy Means of Sour Liquor. 

There are at present two methods in common use by which 
this plumping is accomplished, as has been stated. In one of 
these the tanning-liquor which has been in use for some time 
is made use of under the name of " tailings," or sour liquor, and 
in which the hide having been properly prepared is first placed. 

The fresh tan-liquors after a short time become changed in 
their character and nature, and the resultant is a liquid in which 
we find tannic, gallic, and acetic acids in varjnng proportions, 
combined with decaying vegetable and putrescent animal matter, 
but the presence of the latter substances seriously interferes with 
the exhibition of those active principles which the tanner seeks 
to utilize from his sour liquors, and it is the presence of this 
decomposed matter that forms the only objection to this method 
of plumping hides, and which gives it the principal danger, 
which, while not great, still requires watchfulness. 

The second method of plumping, and which will be enlarged 
upon in the next section of this chapter, is to steep the hides in 
a cold, dilute, sulphuric-acid liquor. 

But while the latter method expedites the work, it has the 
effect of rendering the leather harsh, liable to be brittle, and 
gives a dark grain to the same, it being conceded by all practi- 
cal tanners that the process in which the plumping is wrought 
by the presence of the acetic or aceto-gallic acid principle in the 
tailings is far preferable, could the same be divested of the 
trouble arising from the decaying animal and vegetable sub- 
stances present in all tanning-liquors which have been used for 
any length of time. 

H. J. Botchford, of Leyden, N. Y., proposes to remedy this by 



HANDLING AND PLUMPING. 361 

subjectiug the soar liquors to a distillation in a still suitably 
constructed, by whicli the acetic and gallic acids are recovered 
in a pure form, freed from the other substances of the liquors. 
The distillate thus resulting is now taken, and, in a properly 
dilute form, is again used as a liquid in which the plumping of 
the hides may be very expeditiously and satisfactorily accom- 
plished. 

In the practical working of this process the distillation is best 
accomplished by the use of a still in which the liquors from 
which the acid products are to be recovered are heated by means 
of a steam-worm coiled within the bodj'" of the retort containing 
the said liquors, the vapors of the acids thus liberated being con- 
ducted from the head of the retort through a tubular condenser, 
the temperature of which is maintained at a sufficiently low point 
for the proper condensation of the acid vapors by surrounding the 
same with water at a low degree of heat; but any apparatus 
ordinarily termed a "still" will answer, as long as its materials 
are arranged to be proof against the attack of the acids to be 
recovered, and the heat of which can be maintained equally. 

Plumping hy means of Sulphuric Acid. 

In 1773, David MacBride, a physician of Dublin, introduced 
the employment of sulphuric acid for swelling or plumping hides, 
and though it may appear strange that such an improvement 
should have been made by a member of the medical profession, 
still this, like many other advances, was the result of accident, 
which arose from a series of experiments carried on for purely 
medical purposes, for confirming a theory that an infusion of 
malt would cure the sea scurvy. 

MacBride for four years kept the matter a partial secret, 
imparting the knowledge to only one firm of tanners in the city 
of Dublin ; but on May 31, 1777, after being at liberty to dis- 
close it he did so in a communication to the Eoyal Society, and 
it is recorded among the Philosophical Transactions. 

Vitriol or sulphuric acid, as it is also termed, is used for 
plumping both lime and sweat stock. The coloring and plump- 
ing of the latter are usually accomplished simultaneously in the 



862 THE MANUFACTUEE OF LEATHEE. 

handlers, the liquor being strengthened after the removal of 
each pack. 

But while vitriol can be employed without danger on limed 
stock, it is desirable to observe caution in employing it upon 
sweat stock in order that it may not be too much swelled, as its 
action is more energetic upon hides which have been subjected 
to the sweating process. 

Some tanners find that it is an improvement to treat sweated 
hides to a weak lime bath, especially when they are to be 
plumped by sulphuric acid. 

The acid is diluted with cold water, and sometimes more or 
less of the old sour tan liquors are employed in conjunction 
with the sulphuric acid in order to hasten the process of pre- 
paring the hides for the tanning proper. 

It is, of course, impossible to give the exact proportion of 
vitriol to be employed in every case ; but the quantity now 
used is about the same as that prescribed by MacBride, more 
than a century ago, viz., to use his own language, "a wine 
pint of the strong spirit of vitriol is sufficient for fifty gallons of 
water to prepare the souring at first; therefore, all you have 
to do in raising sole leather, is only to prepare it beforehand 
in the usual way, and when it is fitted for the souring, mix 
up a quantity of vitriol and water, according to the number of 
hides that you require to have raised, still observing the pro- 
portion of a pint to fifty gallons, which will be enough if the 
vitriol be of the due degree of strength. The hides may lie in 
the souring till you find them sufficiently raised, for they will 
be in no danger of rotting, as they would be in the common 
sourings, which in time might turn putrid and rot the leather, 
whereas the vitriolic liquid keeps off putrefaction." 

In the early use of sulphuric acid by our tanners, an almost 
general lack of knowledge of the nature and effect of the sub- 
stance under certain conditions was largely prevalent, and much 
harm resulted from its injudicious employment in the handlers, 
but while practical experience has done much to aid the tanner 
in obviating disastrous results, there is still much desirable 
knowledge regarding its use in tanning that can result only 
from chemical experiments. 



LAYING- A WAY. 363 

The most concentrated sulphuric acid is a definite combina- 
tion of forty parts sulphuric oxide and nine parts of water, the 
formulas representing it being HjO, S03, or H^So^, and is a color- 
less oily liquid having a specific gravity of about 1,85, of in- 
tensely acid taste and reaction. 

Oil of vitriol has a most energetic attraction for water, it 
withdraws aqueous vapor from the air, and when it is diluted 
with water great heat is evolved, so that the mixture requires 
to be made with a little caution. 

The specific gravity of sulphuric acid being so much greater 
than tan-liquor, it has at all times a strong tendency to settle 
and mark with spots of different colors the grain of the pack, and 
it is only by strict watchfulness that this can be avoided, and 
when vitriol is added to the pack, it should be done before the 
sides are thrown in, and the plunging should be faithfully per- 
formed in order to prevent the discoloring of the grain by the 
settling of the acid. The swelling or " plumping" process is, 
for the reasons previously stated on page 167, accelerated, and 
the falling back of the hides into their previous state prevented 
by the use of hard water. 



CHAPTER XIX. 

LAYING-AWAY. 

The hides having been raised, the texture dilated, and therefore 
weakened, and being deprived of that natural gum which ab- 
sorbs moisture, are in a condition to be tanned, that is, to have 
their fibres strengthened and re-united. 

Tannin is, therefore, an astringent and impregnating sub- 
stance, by the agency of which the fibres maintain their inde- 
pendence and the faculty, as it were, of sliding one upon another 
in their moist state, and by the means of which, also, the dried 
leather is rendered manageable and elastic. 

Without tannia the skin becomes horny as it dries, and loses 
all elasticity and malleability, which is due to the fact that the 



364 THE MANUFACTUEE OF LEATHEE. 

bandies of interwoven and compact fibrous cellular tissue, of 
which it is composed, stick together, and constitute then a con- 
tinuous, semi-transparent mass. 

Leather is probably not, as has been heretofore considered, a 
chemical combination of the animal substance with the tanning 
substance ; for the reason that the latter is never absorbed in equal 
proportions, but in variable quantities, according to the concen- 
tration of the liquid and the nature of the dissolvent. " One 
may even obtain leather by the sole use of fatty substances, for 
which there can be no question of a chemical combination with 
the animal tissue. Mr. Knapp has even succeeded in tanning 
or making leather without tanning elements. Starting from 
this principle that the filaments adhere or stick together only 
Avhen they are swollen by water, he has put the hide in contact 
with such a liquid as alcohol or ether, which, expelling the 
water by endosmosis, deprives the fibres of their faculty of stick- 
ing. He has obtained in this way a tawed skin, of a nice white, 
and having all the physical qualities of tawed hides. The same 
result is obtained by suspending a cleansed skin in anhydrous 
ether placed above a layer of chloride of calcium. The water 
with which it is impregnated diffuses itself in the ether and is 
gradually absorbed by the chloride of calcium. Any leather 
thus prepared — the only difference in which from the moist hide, 
dried and horny, consists in the physical state of the fibres 
which have kept their independence — becomes an ordinary skin, 
with all its qualities, as soon as it is moistened. 

" It results from these interesting experiments that tanning is 
based rather on a physical action than on a chemical reaction. 
The tanning substances, penetrating the hide by endosmosis, 
envelop the fibres, adhere on their surface through an attrac- 
tion similar to that which causes the precipitation of coloring 
matters on the surface of textile fibres. The fibres thus sur- 
rounded by a layer of foreign matter do not adhere any more 
in drying. 

" The faculty which the tanning substances possess besides, 
of rendering the leather imputrescible, is independent of their 
physical action.' It may disclose itself more or less energeti- 
cally, according to the more or less antiseptic nature of the com- 
pound used. 



LAYING-AWAY 



365 



" A very interesting experiment of Knapp shows besides tliat 
one maj^ compare the leathers, as regards the solidity of the 
tanning with dyed tissues, some of which are of good tint and 
others of false tint. 

"Thus the hides tanned with tan-bark resist the action of. 
water, while those prepared with the tannin of the gall-nut 
come back to the state of untanned hide, after a prolonged 
wash with carbonate of soda, which proves that the active sub- 
stance of tan is not entirely identical with gallotannic acid."^ 

Following this theoretic discussion we shall now proceed with 
the final step in the process of tanning heavy hides and skins, 
such as are employed for sole and upper leathers, etc., which is 
the laying-away of the stock. The usual size of the lay-away 
vats for sole leather hides is nine feet long, seven feet wide and 
six feet deep, and in these the stock is usually placed with the 
grain side up in order to avoid " hook marks" in removing 
them. 

Fis. 118. 




Fig. 118 shows the manner in which the stock is laid away, 
it being spread out smoothly and upon the bottom of the tan- 
vat, and between each layer there is sprinkled a slight thickness 



1 Wurtz. Dictionnaire de Chimie, Pure et Ap^jliquee, iii., 193 et.seg. 



366 THE MANUFACTURE OF LEATHER. 

of ground bark until the vat is filled by the stock and bark 
thus laid in stratum super stratum. 

Tan-liqnor is then run into the vat, and when the interstices 
are filled the whole is crowned with a layer of bark which tan- 
■ ners call a " heading." 

Formerly the inter-laying layers of bark were depended upon 
to do the tanning ; but at the present time in this country the 
bark-liquor is relied upon and not the interlaying bark. In 
European countries the layers of ground bark are still gener^ally 
depended upon to do the tanning, and the time is consequently 
longer than with us. 

In the early stages the green stock requires more attention 
than when it is nearly tanned, as at first it absorbs the tannin 
very rapidly and then gradually its capacity for absorption 
grows less until at the finish it refuses further to imbibe the 
tannic acid, and, as has been stated on page 129, the skins do 
not absorb an unlimited quantity of tannin, and are probably 
not improved by remaining a long time in the vat. 

The number of layers and the period of each differ for the 
various leathers, and depend upon the substance and weight of 
the stock, the strength of the liquors to which it is subjected, 
the season of the year and various other appendant matters ; 
but it is not uncommon in this country to tan the heaviest sole- 
leather in four layers of the following periods, the liquors at the 
end of each stage being of the indicated degrees of strength, 
which gradually increase from say 6° at the start, to about 30° 
at the finish : — 

1st layer, 12 days 16° 

2d " 18 " ..... 20° 

3d " 24 " 25° 

4th " 36 " ..... 30° 

Making the whole period ninety days, and in some cases it 
has been accomplished in much less time. 

In order to obtain full weight and brighter color the time of 
the final layer is prolonged, for when insufficient time is allowed 
to this layer there will be lack of solidity and the grains will be 
inferior. 

In the manufacture of finer grades, such as oak-tanned 



LAYING-AWAY. 367 

sole leather of tlie kind wliich is used for the soles of ladies' and 
children's shoes, the packs are generally laid-away five times. 
'New liquors, or mixtures of new and old, are preferable for dry 
hides, old liquors for slaughtered. "When laid-away in bark 
the packs are changed, as has been stated, until tanned. Much 
care and judgment are necessary in proportioning the continu- 
ally increasing strength of the liquors to the reqairements of 
the leather in the different stages of the process. The liquors 
should also be kept as cool as possible, within certain limits, 
and ought never to exceed a temperature of 80° F. Too high 
a heat, with a liquor strongly charged with the tanning princi- 
ple, is injurious to the life and color of the leather, and the use 
of a too weak one must also be avoided. Hides treated with 
liquors below the proper strength become relaxed in their tex- 
ture and lose a portion of their gelatine. The leather loses in 
weight, and is much more porous. The greatest strength of 
liquor used for handling should not exceed 16° by the barko- 
meter ; and that employed in laying-away should mark at its 
greatest strength from 80 to 35°. 

It is the custom, when the liquors in the lay-away vats are 
gradually increased in strength, to remove the packs after the 
stock has laid-away long enough, and run the ooze through 
wooden pipes into a receiver, and from thence to pump the 
liquor back to the leaches where it passes through the bark and 
is restrengthened, and then run as new liquor into the vats. 

Another method is to allow the fresh and strongest liquor 
direct from the leaches to pass first upon the head packs of the 
last layer, and from thence to the next, and so on through all 
the layfers, and of course decreasing in strength and becoming 
more acid until finally it passes upon the first lay-aways, or 
into the handlers where it is exhausted. 

When this method is employed the liquors when they come 
from the leaches should be at least 30° and ought not to exceed 
35° in strength ; but the liquor should never in the end be 
allowed to remain upon the stock after its strength is spent. 

When heat is used on the head leaches the liquor sometimes 
enters the lay-away yard in a hot condition, and the intent is of 
course to turn it into the head lay-away ; but sometimes the 
attendant by mistake allows it to run on the green stock, thereby 



368 THE MANUFACTURE OF LEATHEE. 

causing damage to the leather, as the " black rot" will be certain 
to set in to a greater or less extent, especially in the heated sea- 
son of the year. 

In tanning heavy upper leather the practice among some of 
our best tanners is to first handle the sides on sticks for ten or 
twelve days, and then lay them away twice in bark both lay- 
aways generally extending over a period of about sixty days, 
the first lay-away being for about twelve days and the second 
for about forty-eight days. After this the sides are split and 
then, after being levelled off, the sides, twentj^-five at one time, 
are placed in a large revolving wheel and worked for about ten 
minutes with moderately strong gambler liquor. From thence 
the sides go again into the handlers, but this time without 
sticks, and are drawn each day for about fifteen days. This 
completes the tanning of the upper leather, and it is then ready 
for the scouring and finishing. 



CHAPTER XX. 

SPLITTING LEATHER. 

After the sides have been removed from the lay-away vats 
they are — in the manufacture of upper leather and some other 
varieties of leather — hung on poles in the yard of the tannery to 
harden, and then carried to the cellar and dampened prep'aratory 
to being split. For other, and more minute details in relation to 
splitting leather the reader is referred to the chapters treating 
of the manufacture of upper and buffed leather. 

Fig. 119 shows an interior perspective view of the cellar of an 
upper-leather tannery. Piles of sides that have been dampened, 
and in condition to be split are shown at 1 and 4. The three split- 
ting; machines in a line, marked 2, are known as the Union- 
Splitting Machines; the one in the background marked 3, is the 
Belt-Knife Machine. The manner in which power is supplied 



SPLITTING LEATHER. 369 

to the machines by means of a line-shaft is shown, the line-shaft 
being marked 5. 

For those who are building or equipping tanneries, views of 
this kind contain many valuable suggestions, as those in this 
work were taken under the author's personal supervision from 
the most modern and concededly the best arranged tanneries in 
the United States. The view shown in Fig. 119 is from the 
tannery of Mr. Thomas E. Proctor, Peabody, Mass. 

Splitting Machines. 

Early in 1831 Alpha Richardson, of Boston, Mass., patented 
his first splitting machine for leather. 

Seth Boyden, of Newark, N. J., had nearly a quarter of a cen- 
tury previous to this invented a machine for this purpose ; but 
while a large number of machines of this character had come 
into use there were numerous objections to them which it re- 
mained for Richardson to overcome. 

He gave great attention to the perfection of his contrivance, 
and continued to improve it until 1856, when he combined all 
his patents in the "Union Splitting Machine," which is now in 
such general use. 

Since the successful introduction of splitting machines hides 
have been split to meet all required conditions, and they may 
be split either in a green or tanned condition. 

In the manufacture of heavy upper leather, as is fully ex- 
plained in the chapter on that subject, the sides are split after 
being only partially tanned. 

When it is desired to split whole hides, as in the manufacture 
of enamelled leather for carriage tops, etc., a machine constructed 
on a different principle is employed. The one in most common 
use for this purpose is known as the "Belt-Knife Splitting 
Machiiie," which was invented in 1854 by Joseph F. Flanders 
and Jere A. Mardenof Newburyport, Mass., and which machine 
is now manufactured by The American Tool and Machine Co., 
Boston, Mass. 

The facilities afforded by machines of the character that have 
been mentioned, allow good " grain splits" to be obtained, which 
are used very largely for shoes, and also for harness,, trunks, 
24 



370 



THE MANUFACTUEE OF LEATHER. 



etc., and the large production of buffed and grain leathers, which 
are now so much used in this country, and form an important 
item in our export list, has been greatly aided by them. 



Fig. 120. 




Fie. 121. 




Fig. 120 shows a perspective view of the A. Richardson or 
Union Splitting Machine, geared so as to be run by steam power, 
and Fig. 121 is a perspective view of the hand power machine, 
and the operation of splitting the side of leather is the same in 
both cases. 

The leather to be split, after having been properly dampened, 
is drawn between the knife and roller. In Fig. 121 A is the 



SPLITTING- LEATHER. 



371 



cast-iron piece connected with the gauge-roller jB, which revolves 
on the centres e e, and is turned up by the lever o, to allow the 
placing of the leather npon the top of the knife and back-spring 
A A. The skin being in right position, the gauge is then turned 
back, and forms the gauge for the thickness of the skins which 
may be regulated at will, by means of the screws h h. Bis the 
roller with the sectional tubes g g g, which are arranged to turn 
on its end, and to serve as friction-rollers when the shanks and 
loose parts of the skin are being drawn through. The knife D 
is bolted firmly to the bed by the screws i i % i. The leather 
is placed upon the cylinder (7, and drawn through against the 
knife D by the aid of the crank at the end of the machine. 

A modification of this machine is shown in Fig. 122, and is 
used largely for splitting and skinning heads, etc., in the manu- 
facture of sole leather, and upper leather, and for welt leather, 
and stiffenings for boots and shoes. 

Fig. 122. 




The machines shown in Figs. 120 to 122 operate by means of 
rollers, which force the leather against the edge of the knife. 

A is the gauge-roller, which is regulated by screws according 
to the thickness it is desired to split the skin. B is the lower 
roller, which forces the leather, or hide, against the knife, and 
the two are put in motion by the crank or pulley as the case may 
be at the end. 

Fig. 123 shows a perspective view of an attachment patented 
in 1883 by John A. Enos, to prevent injury to the arms of those 
who operate the ordinary splitting machines of the character 
which have been described above. 

As generally practised in the factories of New England, 
where leather-splitting is carried on largely, the leather is held 



372 



THE MANUFACTUEE OF LEATHER. 



pressed against and wrapped around the drawing-roller bj the 
hands of the operator, who is in great danger of being caught 
and having his arms broken, such accidents being of very fre- 
quent occurrence. 



Fia:. 123. 




Machines have also been made in which the leather has been 
drawn or fed against the edge of the knife or cutter by a pair 
of cylindrical rolls which act upon the opposite surfaces of the 
leather, pinching it between them ; but when a stationary knife 
or cutter is employed, it is claimed that it has been found im- 
practicable to use such a pair of feeding-rollers, as their holding 
power is not sufficient to draw the leather uniformly against 
the edge of the cutter. Enos discovered that by fluting or 
corrugating the surfaces of the drawing or feeding rollers, and 
preferably also gearing them together, so that the projections 
or convex portions of one roller will fall within the recesses or 
concave portions of the other roller, it is possible to obtain suffi- 
cient holding power upon the leather to draw it properly 
against the edge of the knife and split the leather. 

Enos's invention is shown in detail in Figs. 124 to 126, and 
consists, essentially, in the combination, with the usual splitting 
knife and parts co-operating therewith to present the leather 
properly to its edge, of a fluted or corrugated drawing roller and 
a corrugated or fluted auxiliary or gripping roller, and mechan- 



SPLITTING LEATHER. 



373 



ism hy which the operator can force the rollers against the 
leather between them. 

In the present embodiment of this invention the gripping 
roller is mounted in bearings upon pivoted arms which are 
acted upon bj an actuating-treadle to draw the gripping roller 

Fis. 124. 




Fig. 125. 



Fig. 12(1. 





toward the drawing-roller, and the gripping roller is drawn 
back or retracted bj its own weight or other suitable retractor, 
so that the operator hy merely raising his foot can at once re- 
lieve the pressure on the leather, which will then cease to be 
drawn. 



ST-i THE MANUFACTURE OF LEATHER. 

Fig. 124 is a front elevation of a leather-splitting machine 
embodying Enos's invention ; Fig. 125 an end elevation thereof; 
and Fig. 126 a vertical section on line x .t, Fig. 124. 

The framework a, knife 5, and mechanism for presenting the 
leather to be split to the knife-edge may all be of any usual 
construction, these parts not constituting the present invention. 
The leather presented to the knife at a short distance from the 
end of the piece or side has its end carried over the corrugated 
or fluted drawing-roller e, mounted on a shaft /, shown as actu- 
ated by a gear, g^ meshing with a pinion, A, on a shaft, ?", hav- 
ing the usual fast and loose pulleys for the driving-belt. Thus 
by wrapping the leather around the roller e, or pressing it 
against the surface thereof, the leather will be drawn against 
the edge of the knife and split by the power by which the 
roller is rotated, although it is necessary, in addition to the 
power, to provide means for holding the leather upon the sur- 
face of the drawing-roller. This is accomplished in accord- 
ance with the present invention by the auxiliary or gripping 
roller rn^ having its bearings in carrying-arms n^ pivoted on the 
shaft 0, so that the roller can be swung or oscillated upon, the 
arms toward and from the roller e. The arms n have exten- 
sions n\ forming therewith a bent actuating-lever for moving 
the roller m toward the roller e, the extensions or arms n' being 
provided with counterbalance-weight:^ w^ for partly balancing 
the weight of the roller m. The arms n' are connected by links 
or rods p with the actuating-treadle ?', so that the operator, by 
depressing the treadle, forces the roller m toward the roller e to 
grip the leather between them. The roller m is corrugated or 
fluted to correspond with the roller e, as shown in Fig. 126, and 
the roller e is provided at one end with a gear, s, meshing with 
an intermediate, ^, that meshes with a pinion, t\ fixed upon the 
shaft 0, which has at its other end a pinion, w, meshing with a 
gear u' ^ connected with the roller m. The gears s and u' are of 
the same size, and the pinions t t" u are of uniform size, so that 
the rollers 7>i and e rotate in unison in opposite directions and 
the projections of the one roller fall into the recesses of the 
other. The two rollers thus co-operate to grip and draw the 
leather, which passes down between the rollers instead of being 



SPLITTIN"G- LEATHER. 375 

wrapped around one roller, as in the machines heretofore em- 
ployed. By the employment, in connection with a fluted draw- 
ing-roller actuated by power in the usual manner, of a corres- 
ponding fluted auxiliary roller — or, in other words, a co-operating 
pair of fluting, gripping, and drawing rollers — the danger to the 
operator, it is claimed, is removed, and the operation and capa- 
city of the machine for splitting the leather are improved and 
increased. 

In the old machines employing but a single roller, the leather, 
when wrapped around it, frequently forms bunches, causing in- 
equality in the tension of the leather, and consequent inequality 
in the thickness of the split material. 

McDonald and Beygs'' Leather Splitting Machine. 

The leather-splitting machine shown in Figs. 127 to 131 is 
the invention of John D. McDonald and William Beggs, of 
Woburn, Mass., and the invention relates to a leather-splitting 
machine of that class in which the leather to be split is drawn 
by a suitable drawing-roller against the edge of a stationary 
knife, the thickness of the split being regulated by a pressing 
or gaging roller, the periphery of which is just above the edge 
of the knife, against which it holds the leather being drawn, so 
that the thickness of one portion of the leather is equal to the 
distance between the edge of the knife and the periphery of 
the roller. 

In leather-splitting machines as heretofore constructed the 
gaging-roller has usually been mounted to turn loosely upon its 
arbor or bearings, so as not to resist the movement of the leather 
beneath it. 

The present invention consists in the combination, with the 
pressing or gaging roller, of means to rotate it positively for as- 
sisting in feeding the leather against the edge of the knife, and 
thereby reducing the work of the usual drawing roller. The 
gaging-roller is mounted in the usual beam, which is pivoted to 
enable the roller to be lifted up away from the knife to facilitate 
the introduction of the piece of leather to be split, and in this 
embodiment of the invention the roller is provided with a pin- 
ion meshing with a pinion upon a shaft coincident with the axis 



376 



THE MANUFACTURE OF LEATHER. 



Fig. 127. 




F]V. 128. 



Fis. 129. 





Fig. 130. 



Fio". 131. 





SPLITTING LEATHER. 377 

of rotation of the beam, and provided with a pulley and clutch- 
ing device whereby the movement of the gaging and feeding- 
roller may be controlled as desired. A locking device for the 
beams prevents it from being turned on its pivots by the reac- 
tion of the roller in feeding the leather. 

Figure 127 is a front elevation of a leather-splitting machine 
embodying this invention ; Fig. 128, an end elevation thereof; 
and Figs. 129, 130, and 131, sectional details on lines a?, ?/, and z, 
Fig. 127, the beam being shown in Fig. 130 as turned to the 
position to raise the gaging-roller for the introduction of the 
leather. 

The frame-work a, leather-supporting bed or table Z>, knife c, 
drawing-roller c/, and its actuating-gears e e', the latter mounted 
on the main actuating shaft/, provided with a pulley /', are all 
of usual construction. The machine is also provided with the 
usual beam, A, pivoted to turn on bearings at A', it being oper- 
ated by a handle, t, and carrying the gaging-roller /<:;, by which 
the leather is held against the edge of the knife c and the thick- 
ness of the split regulated, the bearings of the beam h being 
adjustable by screws li^ to determine the thickness. When 
the beam is turned down to bring the roller ^' into operative 
position, its movement is limited by the toe A^, engaging the 
adjustable stop li'^. (See Fig. 129.) 

In order to cause the roller h to operate also as a feeding- 
roller to assist in forcing the leather against the edge of the 
knife in accordance with this invention, the roller is provided 
near one end with a pinion, m, meshing with a pinion, n, upon 
the roller-actuating shaft o, concentric with the bearing of the 
beam A, so that the rotation of the latter to raise and lower the 
roller ^, as shown in Figs. 130 and 181, does not disengage the 
pinions. The shaft o has loose upon it a pulley, p, actuated by 
a suitable belt, and having its hub made as one portion of a 
clutch, the co-operating portion r of which is splined upon the 
shaft, and is moved longitudinally there on to engage and dis- 
engage the clutch by a shipping-lever, s, connected by a link, ^, 
with a treadle, w, at the front of the machine. Thus when the 
treadle is depressed the clutch is engaged and the pulley |) made 
to connect with the shaft to rotate it, and, through the pinions 



378 THE MANUFACTURE OF LEATHER. 

in w, to rotate the roller h in the direction to force the leather 
against the edge of the knife. By positively rotating the roller 
h so as to feed the leather, the roller is itself forced backward, 
tending to turn the beam h from the position shown in Fig. 129 
toward that shown in Fig. 130, and such movement is prevented 
by a locking device, shown as a pin, Iv' (see Figs. 127 and 129), 
made laterally adjustable by set-screws A", and adapted to be 
engaged by the end of the shipper-lever s when moved to throw 
the clutch into engagement, and thus apply the power to the 
roller. If desired, such a locking device may be applied at the 
other end of the beam U. 

The Belt- Knife Splitting-Machine. 

Fig. 132 represents a perspective view of the belt-knife split- 
ting-machine, which has already been mentioned, and the one 
shown is the common size employed for splitting sides of leather, 
the knife presenting a cutting edge of fifty-seven inches. The 
manufacturers make another size, the knife of which presents a 
cutting edge of seventy-two inches for splitting whole hides, as 
for the manufacture of enamelled leather. 

These machines are successfully employed on all varieties of 
leather. 

If proper attention is given to the knives of these machines 
there is not much liability of annoyance from the other parts, 
and it is necessary to see that the operatives use proper care in 
the adjustment of the knife on the machine, and that they es- 
pecially avoid pinching it too tightly within the jaws. It 
should also be observed that the knife wheels are kept true, 
and that they are about 2-V ^^ ^'^ inch larger in diameter near 
the flange than they are at the opposite edge. The wheels, 
when new, are in this form, but, after a time they get worn and 
require to be newly turned. It is also extremely important 
that the axle of each wheel presents the same angle to the knife, 
so that two lines drawn across the edges of the wheels will meet 
in the centre between the wheels. By observing these direc- 
tions there will be but little occasion for mending knives. We 
here take the opportunity to say that a broken knife less than 



SPLITTING LEATHER. 



379 




two inches in width, is not worth mending, as a knife that is 
broken at one place, is frequently at the point of breaking in 
many places. 



380 THE MANUFACTURE OF LEATHER. 

Eustace Gummincjs' s Iimq^rovement in Belt-Knife 
Splitting -Machines. 

Heretofore in leather-splitting machinery having a belt-knife 
the sides of leather have been fed to the knife by means of the 
feed and gage rolls arranged in front of the cutting-edge of the 
knife, and the operator simply guides the same as it leaves the 
knife and examines it from time to time to see that it is being 
split to the proper thickness. Cummings claims to have dis- 
covered that by the addition of drawing mechanism placed upon 
the opposite side of the belt-knife from the feed-rolls, which 
shall produce a constant and uniform tension upon- the leather 
as it is being drawn from the knife, that it can be much more 
uniformly split than would otherwise be the case. In fact the 
inventor strongly claims that a substantially perfect result is 
reached in that the leather is split uniformly or of the same 
thickness throughout, this result being obtained because it is 
drawn and held firmly to the gage-roll. 

Figure 133 is a back or rear elevation of a belt-knife machine 
such as made by Barton & Co., of Boston, Mass., containing 
Cummings's invention. Fig. 134 is a side elevation, and Fig. 
135 is a vertical cross-section. 

A represents the belt-knife. It is revolved by means of 
driving wheels or pulleys in the ordinary way. 

h b' W represent the ordinary feed-rolls of the Barton machine. 
The roll 5 is a rubber-covered roll, which revolves the smaller 
sectional roll l'^ and the leather is fed between this smaller sec- 
tional roll and the gage-roll JJ^ to the knife. It is of course 
apparent that there is a space between the cutting edge of the 
knife and the portions of the rolls which almost impinge, and 
which is sufficient to cause the leather to be pressed from a 
straight path and down from the gage- roller as it is being fed 
to the belt-knife, and it is this movement from a straight line 
that causes the leather to be split unevenly. It is equally ap- 
parent that if the leather be drawn taut upon the knife this 
fulness between the cutting-edge and the feed and gage-rolls is 
prevented. This is claimed to be accomplished in the present 
invention by means of the drawing mechanism, consisting, pre- 



SPLITTING LEATHER. 



381 



Fig. 133. 




Fig. 134, 



Fis. 135. 





ferably, of two rollers C C, positively driven from any suitable 
shaft by means of a belt, c, and pulley c', or in any other desir- 
able way. These rollers are run at a speed greater than the 
speed of the feed and gage-rollers. The lower of the two rollers 



382 THE MANUFACTURE OF LEATHER. 

preferably is covered with rubber, felt, or other like material ; 
but while this is an improvement upon a metal-surfaced roller 
yet the inventor does not wish to be understood as limiting 
himself thereto. The rollers are arranged above the plane of 
the knife, so that the split portion of the leather takes a diagonal 
course upward thereto after leaving the knife. The upper 
roller is provided with a vertical movement in relation to the 
lower roller so that it may be moved to receive the forward 
end of the leather as it passes the knife, and also to permit of 
the adjustment of the leather while it is being split, or, on ac- 
count of its shape (when a side), it does not feed uniformly in 
a straight line. This is accomplished by means of the sliding 
boxes D B\ the rods d^ the lever d\ connecting-bar d^^ and the 
treadle #, and it is preferable that the construction be such 
that the upper roller shall automatically lift from the lower 
roller, and this may be accomplished either by counterbalanc- 
ing weights rf*, attached to the bar d^^ or b}^ means of springs 
adapted to lift the treadle and the upper roller. In this case the 
front portion of the side of leather passes the knife, enters 
between the two rollers, and the operator then with his foot 
presses the upper roller down upon the leather and lower roller 
sufficiently to give as much tension or friction thereon as may 
be desired, and as the rollers revolve faster than the feed-rollers 
the leather is drawn taut between the feed and drawing rollers 
and upon a straight line parallel with the rollers, but somewhat 
inclined between the drawing-rollers and the feed-roller. The 
teeth of the gear-wheels upon these rollers are made long, so 
that a separation of the rollers can take place without interfer- 
ing with the positive rotation of either roller, so that when the 
upper roller is brought down upon the sides it will be rotating 
at the same speed as the lower-roller. 

By this device Cummings claims to be enabled to split the 
leather to a uniform degree of thickness, and thereby dispense 
with the subsequent shaving now necessary, and consequently 
save the cost of much labor, as well as prevent the waste of the 
stock ; that which before made shavings forming a portion of 
the split leather, and of course making it stronger, heavier, and 
of better quality. 



SPLITTING LEATHER. 



383 



It is not necessary in all kinds of work to use both drawing- 
rollers, as the lower one, especially when covered with a fric- 
tional material, like rubber, will answer to draw the hide, 
especially when held down thereon by hand. 



List of all Patents for Leather Splitting Machi 
ment of the United States of America, from 1 



nes, issed by the Govern- 
790 to 1883 inclusive} 



No. 


Date. 




luventor. 


Residence. 




July 9, 


1808. 


S. Parker, 






Jan. 7, 


1809. 


S. Boyden, 


Newark, N. J. 




April 26, 


1809. 


S. Parker, 






July 12, 


1810. 


P. Dow, 


Boston, Mass. 




April 5, 


1813. 


S. Parker, 






May 3, 


1820. 


E. Howard, and 
J. Butters, 


Boston, Mass. 




May 31, 


1822. 


J. Butters, 


New York, N. Y. 




April 23, 


1831. 


A. Richardson, 


Boston, Mass. 




Dec. 31, 


1833. 


J. P. Shaw and 
J. C. Briggs, 


Boston, Mass. 


1,010 


Nov. 20, 


1838. 


E. Putnam, 


Danvers, Mass. 


1,272 


Aug. 2, 


1839. 


H. White, 


Binghamton, N. Y. 


1,967 


Feb. 9, 


1841. 


A. Richardson, 


Boston, Mass. 


3,541 


April 17, 


1844. 


A. Richardson, 


Boston, Mass. 


5,456 


Feb. 22, 


1848. 


J. P. Fairlamb, 


Wilmington, Del. 


8,227 


July 15, 


1851. 


W. Panton, 


Milton, Mass. 


8,369 


Sept. 16, 


1851. 


A. Richardson, 


North Enfield, N. H. 


9,980 


Aug. 30, 


1853. 


C. Weston, 


Salem, Mass. 


11,604 


Aug. 29, 


1854. 


J. F. Flanders and 
J. A. Mar den. 


Newburyport, Mass. 


12,114 


Dec. 9, 


1854. 


E. Pratt, 


Salem, Mass. 


12,392 


Feb. 13, 


1855. 


M. H. Merriam and 
J. B. Crosby, 


Chelsea, Mass. 
Stoneham, Mass. 


13,407 


Aug. 7, 


1855. 


J. B. Tay, 


North Woburn, Mass, 


13,756 


Nov. 6, 


1855. 


J. A. Marden and 
H. A. Butters, 


Newburyport, Mass. 
Haverhill, Mass. 


14,430 


Mar. 11, 


1856. 


E. Pratt, 


Salem, Mass. 


22,108 


Nov. 23, 


1858. 


H. E. Chapman, 


Albany, N. Y. 


23,900 


May 10, 


1859. 


D. H. Chamberlain, 


West Roxbury, Mass. 


28,559 


June 5, 


1860. 


D. H. Chamberlain, 


West Roxbury, Mass, 


29,649 


Aug. 14, 


1860. 


J. F. Flanders, 


Boston, Mass. 


30,553 


Oct. 30, 


1860. 


S. S. Turner, 


Westborough, Mass. 



1 This list does not include skinning and leather splitting machines used in 
the manufacture of boots and shoes, only those used in tanneries and currying 
shops. 



384 



THE MANUFACTURE OF LEATHER. 



jVo. 


Date. 




Inventor. 


Residence. 


31.746 


Mar. 19, 


1861. 


J. A. Safford, 


Boston, Mass. 


35,850 


July 8, 


1862. 


A. H. Van Gieson, 


Newark, N. J.. 


38.763 


Juue 2, 


1863. 


B. Rowe, 


Albany, N. ¥. 


39,695 


Aug. 25, 


1863. 


H. Wing, 


Buffalo, N. Y. 


41,448 


Feb. 2, 


1864. 


J. A. Safford, 


Boston, Mass. 


43,]59 


Juue 14, 


1864. 


C. S. Stearns, 


Marlborough, Mass. 


53,741 


April 3, 


1866. 


J. A. Marden, 


Newburyport, Mass 


53,771 


April 10, 


1866. 


C. W. Baldwin and 
L. D. Hawkins, 


Charlestown, Mass. 
Stoneham, Mass. 


54,043 


April 17, 


1866. 


A. H. Van Gieson, 


Newark, N. J. 


54,571 


May 8, 


1866. 


J. A. Marden, 


Newburyport, Mass 


70,175 


Oct. 29, 


1867. 


A. Dawes, 


Hudson, Mass. 


74,734 


Feb. 18, 


1868. 


F. J. Vittum, 


Newburyport, Mass 


75,823 


Mar. 24, 


1868. 


J. H. Abbott and 
J. A. Marden, 


Maiden, Mass. 
Boston, Mass. 


78,697 


June 9, 


1868. 


C. S. Stearns, 


Marlborough, Mass. 


83,888 


Nov. 10, 


1868. 


J. Taggart, 


Boston, Mass. 


95,780 


Oct. 12, 


1879. 


H. Cunningham, 


Albany, N. Y. 


98,068 


Dec. 21, 


1869. 


C. Keniston, 


Somerville, Mass. 


98,888 


Jau. 18, 


1870. 


J. A. Safford, 


Winchester, Mass. 


100,082 


Feb. 22, 


1870. 


C. S. Stearns, 


Marlborough, Mass. 


123,589 


Feb. 13, 


1872. , 


C. S. Stearns, 


Marlborough, Mass. 


139,744 


June 10, 


1873. 


A. F. Stowe, 


Worcester, Mass. 


144,899 


Nov. 25, 


1873. 


J. Goebel and J. Preis 


, Caledonia, Wis. 


147,172 


Feb. 3, 


1874. 


G. Reynolds, 


Woburn, Mass. 


149,542 


April 7, 


1874. 


C. S. Stearns, 


Marlborough, Mass. 


156,652 


Nov. 10, 


1874. 


J. A. Safford, 


Winchester, Mass. 


179,948 


July 18, 


1876. 


H. F. Osborn, 


Newark, N. J. 


191,855 


June 12, 


1877. 


J. Hodskinson, 


Salem, Mass. 


209,001 


Oct. 15, 


1878. 


A. E. Whitney, 


Winchester, Mass. 


211,187 


Jan. 7, 


1879. 


J. A. Safford, 


Boston, Mass. 


230,895 


Aug. 10, 


1880. 


J. A. Safford, 


Boston, Mass. 


244,196 


July — , 


1881. 


C. Daneel, 


New York, N. Y. 


278,562 


May 8, 


1883. 


J. E. Enos, 


Peabody, Mass. 


279,659 


June 19, 


1883. 


J. D. McDonald and 
W. Beggs, 


Woburn, Mass. 


288,551 


Nov. 13, 


1883. 


E. Cummings, 


Woburn, Mass. 



PART yi. 

CHAPTEE XXI. 

scouumG. 

After the leather has been split it is commonly handled in 
liquor for about two weeks, which completes the tanning pro- 
cess, and the next operations to Avhich it is to be subjected are 
the drying and finishing for market. 

Of course different varieties of leather pass through different 
modes of treatment, and while there is but little to be done in 
the finishing of sole leather, except the drying and rolling, there 
is much to be done in finishing upper leathers, Morocco leathers 
etc. 

We shall therefore devote one chapter to each of the subjects 
of scouring, stuffing, blackening, and polishing leather, and then 
for other details of special branches of manufacture and for 
coloring and dyeing leather, refer the reader to the various chap- 
ters treating of those subjects. 

The tools used in the hand method of scouring leather are 
the brush, stone, and slicker ; the brush is shown in Fig. 136, 

Fi^. 136. 



. . llhlPI'i iHI I,'jiIlMiIVIMi#' ^IMt^, 



and the perspective view. Fig. 137, shows the form of tables and 
other mechanical details connected with the hand method of 
scouring leather. 
25 



386 THE MANUFACTURE OF LEATHER. 

This manner is laborious and expensive, which has caused it 
to be superseded almost entirely by machinery. 

Fiff. 137. 




A review of all the leather-finishing machines that have been 
perfected since 1867 will, I think, show none of so much import- 
ance to the tanner and currier as the leather scouring and set- 
ting machines which have, during that time, become so common 
in our tanneries and currying shops. 

Some of these machines are so arranged as to do simply the 
scouring, while others will perform either the scouring or setting. 

Lockivood's Machine. 

The Lockwood Automatic Leather Scourer and Setting- 
Machine, shown in Figs. 138 to 140, is valuable for performing 
the work of scouring all kinds of leather that are thus treated, 
or for setting calf-skins, kip, buff, and wax. 



SCOURING. 



387 




388 



THE MANUFACTURE OF LEATHER. 



It is a costly machine, but its work is so satisfactory that I 
have not heard a complaint against it in the various large tan- 
neries and currying shops, where I have seen it in operation, in 
the neighborhood of Woburn, Salem, Peabody, and other points 
in Massachusetts. 




In one tannery, that of Messrs. Bryant & King, located near 
Woburn, Mass., the author saw seven of these machines setting 
calf-skins, and was much surprised at the ease with which they 
were operated and the excellence of the finished work. 

Fig. 138 shows a perspective view of the Lockwood machine. 

Fig. 139 is a vertical and longitudinal section of the same. 

Fig. 140 is a vertical transverse section of the same. 



SCOURING. 



389' 



The table A is supported upon a stage, B, wliicli is erected 
upon the floor C of the apartment or the foundation of the 
machine, whatever the latter may be ; and the inventor has 
made provision for levelling the table A, or adjusting it to slop*- 



Fiff. 140. 




ing or irregular floors or foundations. In the drawings, the floor 
is represented as sloping and depressed at the rear, which is 
desirable in order that refuse water and liquids may pass off. 

To compensate for the inclination or irregularities of the floor 
G, the inventor prefers to dispose the front ends of the lower 
beams, D, of the stage B, upon metallic blocks, and screw through 



S90 THE MANUFACTUEE OF LEATHER. 

the ends of the beam screws to bear upon the blocks, by which 
means the irregularities or inclination of the floor are overcome. 

In the rear of the table A is disposed an upright truck, K, the 
movements of which are guided by a horizontal rail, L, secured 
to the rear ends of the beams D and parallel to the edge of the 
table. Wheels J/ are interposed between the triick ^ and rail 
L to reduce friction, while a second series of rollers, iV, are 
pivoted to the feet of the truck and roll upon or against the 
front edge of the rail, and serve as rolling bearings to retain the 
wheels Min place upon the rail L and overcome the great fric- 
tion incident to leverage of the truck over the upper rail, P 
(see Fig. 140), as a fulcrum. The inventor pivots to the adja- 
cent parts of truck antifriction rollers Q, which travel against 
the rear edge of the ledge or upper rail, P. 

The trundle-frame i? of the carriage m (shown in Figs. 139 
and 140) is placed between the side pieces, B^ E^, of the hori- 
zontal beam i?' of the truck, and has V-shaped bearings to fit 
correspondingly-shaped grooves a in these side pieces. The 
carriage, composed of the trundle-frame B and vertically-ad- 
justable head m', is moved longitudinally with relation to the 
beam R' and transversely of the table by means of a screw- 
threaded shaft, jS (see Fig. 140), held in suitable bearing, h c, the 
screw fitting a threaded nut, cf, fixed to the rear part of the 
trundle-frame of the carriage. The screw-shaft jS is rotated by 
a bevelled gear, d, fixed to its rear end, which bevelled gear is 
engaged and driven by a second bevelled gear, e, secured to the 
upper end of a vertical shaft,/, which is supported in bearings 
h i, erected on bars j Jc, which unite the side plates or housing, 
T T', of the truck K. 

When the strokes of the tools are to be repeated several 
times in the same direction the handle of the catch is raised and 
that of the latch elevated by the spring 2, interposed between 
the two, the nose of the latch being thereby forced into one of 
the notches y*, and the yoke, with the hand- wheel, is thus locked 
to the annular plate J' of the head of the carriage. Mr. Lock- 
wood's object in thus locking the yoke and hand- wheel is to re- 
lieve the attendant from the manual labor of holding, the guide- 



SCOUEING. 391 

bar y* in a fixed position, which is essential to impart rectilinear 
motion to the tools. 

The tool-holders o* |/, pivoted to the tool-carrier /*, will be 
lifted from the skin during their backward stroke. 

When it is desired that the tool-carrier, with the dressing- 
tools, be moved diagonally across the table, it is necessary to 
simultaneously move both the carriage on the beam B' and the 
truck K on its rails. This is accomplished by moving the 
handle of the guide-lever F' in the direction it is desired the 
tool-carrier to take, the movement of the guide-lever simul- 
taneously turning the rock-shafts (?' W'^ causing the bands 
to rotate two of the pulleys JL', e^, F, or/^, which is necessary 
in order to insure the proper direction of the movement of the 
parts. This hand-operated guide-lever i^', the position of which 
determines the direction of movement of the tool-carrier and 
tools, and the position of the dressing-tools with relation to the 
skin, greatly simplifies the labor of the attendant, places the 
machine more perfectly under his control, and consequently 
enables more and better work to be done. 

The present invention is an improvement on the machine 
which Avas patented by the same inventor in 1876. 

In devising this later machine, Lockwood had in view, first, 
to drive the operative parts of the machine by direct positive 
mechanical devices in lieu of a belt, thereby insuring uniform 
and certain actions of the various agencies and reducing the 
power required to run the machine ; and, second, to relieve the 
attendant to a great extent of the constant care and watchful- 
ness heretofore devolving upon him, and enable the main func- 
tions of the machine to be controlled by a single hand or guide- 
lever. 

In order to obviate the lifting of the beam when the dressing- 
tools are lifted, and to give increased rigidity at the junction of 
the beam-arms and truck, Lockwood has made the beam-arms 
as a fixed part of the truck, and divided the so-called " cross- 
head" or carriage into two parts, one of which we will denomi- 
nate as the "trundle-frame" and the other as the "head." This 
head is made vertically adjustable with relation to the horizon- 
tally-movable trundle-frame, and there is mounted in this head 
the axially-movable yoke having upon it the guide-rod which 



392 THE MANUFACTURE OF LEATHER. 

receives the reciprocating tool-carrier. The head in the present 
invention is made vertically adjustable by means of a hand- 
operated shaft located at the front of the machine, and such ad- 
justment may be made during the operation of the machine. 
The truck is made movable longitudinally with relation to the 
skin-supporting table by means of a rotating nut placed on a 
screw-threaded rod held in a fixed part of the frame-work of 
the machine. This nut may be rotated in one or the other 
direction on the rod, the ends of the nut acting against the 
truck to move the same longitudinally. This nut and screw 
enable the truck to move positively in both directions and 
hold the truck firmly in place, thus dispensing with pawls and 
their actuating mechanism. 

There are also other improvements in this machine over the 
one patented by the same inventor in 1876, such as driving the 
operating parts of the machine, positively by means of shafting 
and gearing instead of belting, and also in substituting a single 
lever in lieu of the double-hand levers for controlling the truck 
on the ways and the so-called " cross-head" and carriage. 

The new Lockwood machine, as will be seen by Fig. 138, 
has a large table on which to place the stock, so that one work- 
man can be preparing a side at one end Avhile the other will be 
directing the machine in the automatic setting out of a side pre- 
viously arranged on the other end. The working thus keeps 
two men constantly busy, but the physical labor required is 
light, for the machine takes all this. The strokes made are 
either strong or light, as desired, being directly under the con- 
trol of the operator, who, with his hand on the wheel, guides 
and almost, as it were, feels them. So, in going over the 
bellies and flanks, working out folds and thoroughly setting out 
thick portions of a side, the work is not only done quickly and 
well, but the leather is made to measure enough more, on all 
stock sold by the foot, to quickly pay for the machine in the 
gain thus made. 

Holmes's Machine. 

The Holmes Scouring, Setting, and Hide-Working Machine 
is shown in Figs. 141 to 145, and is an improved form of the 
old Fitzhenry and Ball, and Pray and Fitzhenry machines. 



SCOUEIISTG-. 



393 




394 



THE MANUFACTURE OF LEATHER. 



Fig. 141 shows a perspective view of the machine in opera- 
tion ; Fig. 142 is a front elevation of the portion of the machine 

Fig. 142. 




embodying Holmes's improvement of March 8, 1881 ; Fig. 143 
is a plan thereof; Fig. 144 is a vertical section on the line x x 
of Fig. 143 ; Fig. 145 is a vertical section, to which reference 
will be made hereafter. 



Fig. 143. 




In operating this machine the hide is laid upon the table, 
which is mounted upon rollers, and provided with universal 



SCOUEING. 



395 



movement on a horizontal plane beneath the head A, and the 
cranks set in motion. This causes the tools to be applied alter- 
nately, according to the direction of movement of the tool head, 
to the skin or leather with a slicking motion. 



144. 




Fig. 145. 



n 


jS 






55 








^^^=^ 




The head or framework A is arranged to be reciprocated 
upon the horizontal and parallel ways a a' by a crank and con- 
necting-rod or pitman, B. This connecting-rod or pitman, or an 
extension thereof, is pivoted at to the head J., and a portion 
extends beyond the pivot, and consequently as the head is re- 
ciprocated, the end V and the point W" are alternately lifted and 
lowered in relation to the line Q of the table upon which the 
hide is scoured, finished, or otherwise treated, and this oscillating 



396 



THE MANUFACTURE OF LEATHER. 



Fig. 146. 




Holmes's Improved Scourixg Machine Parts. 



S. Wrench, f in. and 1|- In. Hexagon. 

2' " f " I in. " 

S. " I " 4 in. Square. 

T. " iin. 

T. " 5-16 in. 

fin. Hexagon Nut. 

7-16 in. " 

I in " " 

7-16 in. X 1 in hardened Set Screw. 

7-16 in. xliin. " " 

7-16 in. x2Hn. " " 

f in. Tap Bolt for Brake Strings. 

I in. s U in. hardened Set Screw. 

4 X 1 in. 

Spring Pins. 

.'i-16ia. X 2 in. Steel Pins, 

f in. X 4 in. 



IS. Brass Lever Nuts. 

19. Levers. 

20. L. H. Slide Brake. 

21. R. H. " 

22. Brake Spring. 

23. .5-16 Brush Pin and Tools. 
21. R. H. Brush Cam. 

25. L. H. " 

26. Brusli Spiral Spring. 

27. Brush Handle. 

28. Brush Top Bar. 

29. Brush Pre.ssure Bar. 

30. Brush Roll Holder. 

31. Brass Back Brush. 
32 Brush Top Screw. 
33. Brush Rod | iu. 
31. Spiral Tool Spring. 



SCOURING. 



397 



movement of this portion of the connecting-rod or pitman in 
relation to the centre b is utilized for the purpose of alternately 
lifting the tools from the work and allowing them to bear upon 
the work. 

The tool-carriers D D' are pivoted or hinged at the points d 
to the head J., and the tool-carrier lifting-rods c?' d} lay hold of 
the tool-carriers and are provided with buft'ers d^ d^. The in- 
ventor connects the nuts or blocks E E' by the long arm or 
lever e, which is pivoted at e' e^ to the blocks. He prefers that 
the lifting-rods d' d^ be provided with a screw-thread, and that 
their position in relation to the blocks E E' be adjusted by the 
nuts e^. 

The tools are held down to their work by means of the con- 
tractile power of the coiled springs F E\ which, at their lower 
ends, are connected with the tool-carriers, as represented, and at 
their upper ends hook upon the rods//', which are adjustably 
secured to the arm or lever e by the nuts/^. 

This construction and combination of springs, tool-carriers, 
lifting-rods, oscillating lifting rod or plate, and connecting lever 



35. 


Spiral Spring Tool Rod 




78. 


Long Right Hand. 






36. 


Stirrup. 










Long Lpft Hand for Latch Screw. 


'V 




37. 


Tool Rod 1 in. 








79. 


Shoit Right Hand Arm. 


T3 




38. 


Flanged Nut 










Short Left Hand for Latch Screw. 


a 




39. 


Rubber Cushion 








SO. 


Bracket Clamp, Left Hand with 




40. 


Handle Rod. 










Stud. 






40i 


. Handle End. 










Bracket Clamp, Right Hand with 


§ 




41. 


Wood Handle. 










Stud 


-■2 




42. 


Table Handle P 


in 






81. 


Latch Spring Holder. 






43. 


Table Handle E 


ar 






82. 


Tap Bolt for SI. 




44. 


Table Handle. 








SX 


Latch Catch Screw. 


a 




45. 


Caster Holder. 




■ 




84. 


Latch Right Hand. 


_o 




46. 


Caster Roll. 








" Left Hand. 


to 




47. 


CastferPin. 




" 


Caster Complete. 


85. 


Latch Spring. 


OS 




48. 


Caster Shell. 




1 




86 


Latch Press Pin. 






49. 


Caster Screw N 


It. 


J 




87. 


Brush Handle Arm. " 


x 




50. 


Elliptic Spring. 








88. 


" " Clamp, Right 




51. 


Stirrup Guard. 










Hand. 




r^ 


52. 


Spring Holder. 










Brush Handle Clamp, Left 


yo p: 


a 


53. 


Pressure Box. 










Hand. 


JSffl 




54. 


Tool Holder. 








89. 


Brush Handle Slide. 


as 


.55. 


Stone Guard. 








90. 


Pressure Screw Ear and Screws. 






.56. 


Water Guard. 








91. 


Spiral Spring Top Lever. 






.57 


f in. Tool and 


sci 


Uato 


r Pin. 


92. 


Pressure Screw. 






58 


Side of Carriage 








93. 


Spiral Spring Nut End. 






59. 


i Top of Carriag 


e. 






94. 


" " Loop End. 






60. 


Oscillator. 








95. 


Slide Brake, U. Slide. 






61. 


Connecting Rod E 


nd. 




96. 


" " Connecting Rod. 






62. 


" " 


St 


rap. 




97. 


Spiral Spring Hook. 






63. 


I* I. 


B 


5X. 












6t. 


a u 


G 


b. 






Parts not Illustrated. 






65. 


" '• 


K 


ey. 




71. 


Wood or Brass Gibs f thick. 






66. 


" " 





lev. 




72. 


Walpole Machine Stones. 






67. 


i( a 


T 


russ Screw. 


■ 73. 


Brass or Steel Slickers. 






68. 


" " 


T 


■usa 


Post. 


74. 


Crank Shaft. 






69. 


Brackett. 








75. 


Pulleys. 






70. 


Slide. 








76. 

77. 


Balance Wheel. 
Post Boxes. 







398 THE MAKUFACTUEE OF LEATHER. 

or arm, give and permit a uniform and equable pressure upon 
the tool-carriers, and consequently upon the tools, at all points 
of their reciprocation or stroke, and this was not the case with 
the mechanism of the old form of these machines. 

For lifting one or both tool-carriers during the reciprocation 
of the head from their work Holmes employs the two pairs of 
rods, G G' and (7^ (r^, arranged so that each pair is supported 
at both ends by independent swinging arms g y\ which are piv- 
oted at y^ to any suitable stationary portion of the device for 
holding the frame a'. One of the two pairs of arms y g' is 
longer than the other pair, in order that each pair of rods may 
be on a different level. Upon each of the inner rods, G' G'^, 
there is arranged a slide, y*, and one of these slides, by means 
of a connecting-rod, c/^, connects with the latch or slide-bar H, 
and the other slide, ^*, by means of a like connecting-rod, ^^, 
connects with the latch or slide-bar H' . Both these slide-bars 
are adapted to be pushed under the lever e, for the purpose of 
holding the tool-carrier from the work when desired. 

Mr. Charles Holmes died shortly after improving this 
machine ; but since the fall of 1883 his estate has continued the 
manufacture of these machines at the old stand in Boston, Mass. 

For the convenience of those owning and operating these 
machines who may desire to order duplicate parts, we show 
them in Fig. 146, 

Fitzhenrif s Machine. 

Figs. 147 to 151 show the latest improvement on the Fitz- 
henry Leather-Dressing Machine, and it consists in the construc- 
tion and arrangement of the devices for raising and lowering 
the tools, and for starting and stopping the same to and from 
the work. 

Fig. 147 is a perspective view. Fig. 148 is a side elevation 
of the steam cylinder and carriage embodying Fitzhenry's in- 
vention. Fig. 149 is a partial longitudinal section of the same. 
Fig. 150 is a transverse vertical section thereof; and Fig. 151 is 
a view of detached parts of the machine. 

A represents the steam-cylinder provided on its sides with 
the grooved ways a, in which the frame or carriage B is moved 



SCOURING. 
Fig. 147. 



899 




Fig. 148. 



A / 




FiR. 149. 



f^ S 




400 



THE MANUFACTURE OF LEATHER. 



back and forth by the piston-rod h passing through both ends 
of the cylinder. In the lower portion of the frame or carriage 
B at each end is a rocking shaft, d, with arms e e projecting out- 
ward therefrom, and to the outer ends of these arms the tool- 



Fig. 150. 



Fig. 151. 





holder G is secured. D is the tool, and E the covering-plate, 
which are fastened to the tool-holder by screws / / passing 
through them. From the back of each rocking shaft d extends 
an arm, A, which is curved upward, as shown, and the upper 
portion slotted or forked and pivoted to a slide, G. This slide 
or sleeve is placed loosely on a bar, H^ to each end of which are 
pivoted two links, i i. The links at one end of the bar H are 
placed loosely on a shaft, m, while the links at the other end 
are secured to a similar shaft m. The two bars JT^with their 
links are so arranged that each shaft m has two links fast 
thereon and two loose links. 

At one end of the frame or carriage B are pivoted two pit- 
men, / /, which connect with and operate two fly wheels, J e/, 
placed on the ends of a shaft, ?z, above the cylinder A in the 
centre. On this shaft are secured two cams, p p, each of which 
operates a lever, Z, pivoted in a slotted bar, P, placed in the 
framework connected to the cylinder. The lower ends of the 
levers L L are, by bars or rods R i?, connected with cranks 5 s 



SCOUKIISTG. 401 

on the shafts m m — that is, one lever connects with one shaft, 
and the other lever with the other shaft. 

When the machine is in operation the shafts m m are rocked 
by means of the cams 2^, levers Z, connecting-bars /?, and cranks 
5, whereby the bars H are moved lengthwise, and alternately 
raised and lowered, thereby alternately raising and lowering 
the tools. 

S is the hand-wheel for swinging the entire mechanism in any 
direction. On the under side of this wheel are two rods, t t^ 
each of which connects with hinged levers V V carrying a 
wedge, W. These wedges are pushed down in grooves at the 
ends of the fulcrum-bars P P to hold them stationary while the 
machine is in operation. To stop the tools it is only necessary 
to push the rods t inward, when the wedges will be drawn and 
the bars or boxes P become movable, thereby removing the 
fulcrums of the levers L so that they will not operate. The 
Avedges W are guided in their up and down movement by 
means of pins x x. 

Burdori's Machine. 

The Burdon Machine is shown in Figs. 152 to 154, and it is 
for dressing, setting out and scouring hides, skins, and leathers; 
and has for its object to facilitate the operation by providing 
for a perfect adjustment of all parts to hides varying in thickness 
and quality. 

The invention consists, chiefly, in the use of a rotating, scour- 
ing, and rubbing cylinder, which is hung in a pendulum-frame, 
so that it can be swung any suitable distance from the bed that 
supports the hide to be dressed. 

Fig. 152 shows a perspective view of the machine, and Fig. 
153 shows a side view, partly in section, of the cylinder and 
elastic bed. 

The scouring cylinder A revolves upon an adjustable and 
elastic bed B^ as shown in Figs. 152 and 153. The scouring 
surface of the cylinder consists of a succession of stones and 
brushes, arranged in alternate rows, and secured to its surface. 
The pressure of the cylinder upon its work is regulated by mov- 
ing the pendulum frame C, in which the scouring cylinder 
26 



402 



THE MANUFACTURE OF LEATHER. 
Fiff. 152. 




SCOUEING. 



403 



revolves towards and from the bed. This is done by means of 
the arms D and E^ which being connected with the treadle F^ are 
at the control of the operator. This latter feature of the machine 
renders it equally applicable to the heaviest sole and belt leather, 
and to the thinnest splits and calf-skins. 



Ym. 153. 




The pendulum frame (7 is suspended from the upper driving- 
shaft, and carries at its lower end a horizontal shaft. A belt 
connects the pulleys for the purpose of transmitting motion to 
the shaft /. 

Upon the shaft /is mounted the scouring cylinder or disk A^ 
which carries the rubbing or scouring implements, in the form 
of stones G and brushes H. 

Each stone is made of triangular or other suitable form, and 
is dovetailed into a dovetail groove of the cylinder J., being- 
locked therein by a wedge or key, c. 

The bed B is arranged above a fixed table Z, and is by springs 
d d underneath, held against and in contact with the scouring 
cylinder. 

The under portion J/ of the bed B is concave, and over it is 
stretched, by being fastened to the ends, a sheet of rubber, 
leather, or other flexible or semi-elastic material. This sheet 
constitutes an elastic cushion, for the material to be treated. 

This is a valuable labor-saving machine ; it removes the bloom 



404 



THE MANUFACTURE OF LEATHER. 



and softens the grain in a thoroughly satisfactory manner, is 
economical in space, requiring only about 6xQ feet square and 
9 feet height. It scours flanks and shanks with as much facility 
as the body of the side, and it does its work equally well on all 
grades and qualities of leather, from the heaviest baud or har- 
ness leather to the finest and lightest calf or goat-skins. It is 
well adapted for the tanyard, cleansing the hide effectually 
from lime and from the bate, and preparing it for the handlers. 
It is also well adapted for removing bloom from sole leather 
after it is tanned, and preparing it for the roller. 

Fig. 154 is a side elevation of the Burdon scouring machine, 
and shows the arrangement and another manner of hinging the 

Fisr. 154. 




table differing from that shown in Fig. 153. In Fig. 154 the 
table is made adjustable by means of levers, and Fig. 154 also 
shows a manner of hinging the spring-bed and combining it with 
the table. 

The scouring-bed if is at one end hinged to a table, N, which 
is by a hinge, a, secured to a fixed platform or floor, 0. 

A set of toggle levers, P, or other suitable mechanism, 
applied against the under side of the table, and connected with 
a treadle or handle, F, can be used to force the table and bed 
with suitable power against the cylinder. 



SCOURING. 



405 



A spring or springs, e, interposed between the free end of the 
bed J/ and the table, serves to hold the bed against the cylinder. 

The upper or contact face of the bed may be made slightly 
concave, as shown, to receive a sheet, B^ of leather, rubber, or 
other material, which is stretched over its ends to constitute a 
cushion surface, upon which the leather to be treated is placed. 

Daheney^s Table for Leather -Scouring Machines. 

Daheney's table for leather-scouring machines is shown in 
Figs. 155 to 159, and the invention has for its object to produce 
a more durable and convenient table than those heretofore used 
for this purpose. The tables usually employed at the present 
time are either of wood or of slate, both of which materials are 
expensive and are rapidly worn out, the table thus having to 
be renewed frequently. 

Fig. 155. 




This table is composed of two metal plates and an intermedi- 
ate strengthening framework connected with the said plates, to 
support them at various points between their surfaces, substan- 
tially as described. 

Fig. 155 is a plan view of a table embodying this invention, 
a portion of the surface-plate being removed to show the sup- 



406 



THE MANUFACTURE OF LEATHER. 



porting framework ; Fig. 156, a side elevation thereof, showing 
the table mounted on rollers or casters in the usual manner ; 
Fig. 157, a partial plan view of a modified form ; and Figs. 158 
and 159, sectional details on lines x and y of Figs. 155 and 157, 
respectively, on a larger scale. 

Fis. 156. 



m 


5 


M^^--^^ 


(mm=^m 


-Its 




(F 


CP <^ ^ 


i? __ It /? 




\ \ 



3 ' 



Fig. 157. 



Fig. 158. 




®S o 



Fig. 159. 




The table consists, mainly, of a surface plate, of thin metal, 
preferably of sheet-steel, and a strong rectangular frame, 6, pass- 
ing wholly around the table and connected with the edges of 
the surface-plate a. As shown in Figs. 155 and 158, the frame 
h has connected with it a series of thin webs or ribs, c, the 
points of intersection of which are enlarged to afford sockets d 
for rivets e, or other fastenings, by which the surface-plate a is 
connected with the framework, the webs with their intersect- 
ing points forming rests to support the thin surface-plate at 
intermediate points or between its edges. 

When the table is intended to be movable upon rollers, as 
shown in Fig. 156, there will be similar surface-plates a at both 
sides of the framework b c d^ the plates being preferably united 
by rivets passing wholly through the table, and being finished 
even with the surface. 

In some cases it will be sufficient if the webs are omitted and 
tubular posts d' used at suitable intervals, as shown in Figs. 157 
and 159, they forming the rests to support the surface-plates a, 



scouRmo-. 



•±07 



and keep them parallel with one another, the posts having pas- 
sages for the shanks of the rivets e, as shown. 

In some instances one surface-plate a only might be used, 
and the plate, together with the strengthening ribs or frame- 
work, might be made from a single piece of metal, although it 
is usually preferable to make the surface- plates independently 
and fasten them upon the stiffening framework. 



List of all Patents for Scouring^ and Setting Machines, issued hy the 
Government of the United States of America, from 1790 to 1883 in- 
clusive. 



No. 


Date. 




Inventor. 


Eesidence. 




Nov. 21, 


1831. 


R. Ernes, 


Boston, Mass. 


17,576 


June 16, 


1857. 


p. E. Hummel, 


Pulaski, N. Y. 


49,606 


Aug. 29, 


1865. 


W. M. Clarke, 


Butternuts, N. Y. 


60,149 


Dec. 4, 


1866. 


F. Davis, 


Lawrence, Kan. 


61,182 


Jan. 15. 


, 1867. 


E. Fitzhenry and 
I. Ball, 


Portland, Oregon. 


61,250 


Jan. 15, 


1867. 


J. A. Pray and 
E. Fitzhenry, 


Portland, Oregon. 


63,307 


Mar. 26, 


1867. 


A. W. Roberts, 


Hartford, Conn. 


65,224 


May 28, 


1867. 


A. Howard and 
G. F. Howard, 


Wellsville, Md. 
Chicago, 111. 


76,619 


Aprilll, 


1868. 


E. Fitzhenry, 


Boston, Mass. 


79,832 


July 14, 


1868. 


A. Howard, and 
G. F. Howard, 


Wellsville, Md. 
Chicago, 111. 


84,001 


Nov. 10, 


1868. 


F. W. Rust, 


Umatilla, Oregonc 


90,664 


June 11, 


1869. 


C. Holmes, 


Boston, Mass. 


98,121 


Dec. 21, 


1869. 


J. T. Melrose, 


Boston, Mass. 


100,387 


Mar. 1, 


1870. 


E. Fitzhenry, 


Boston, Mass. 


101,508 


April 5, 


1870. 


A. W. Reed, 


Schenectady, N. Y. 


102,270 


April 26, 


1870. 


S. Hutchinson, 




105,419 


July 19, 


1870. 


D. P. Burdon, 


New York, N. Y. 


106,439 


Aug. 16, 


1870. 


J. R. Williams, 


Salem, Mass. 


108,782 ) 


Nov. 1, 


1870. 


( H. C. Havemeyer 


New York, N. Y. 


108,783 i 






t and D. P. Burdon, 




114,809 


May 16, 


1871. 


D. Harrington, 


Boston, Mass. 


117,921 


Aug. 8, 


1871. 


J. C. Parmerlee, 


Bean Blossom, Ind, 


118,002 


Aug. 15, 


1871. 


E. Fitzhenry, 


Boston, Mass. 


118,003 


Aug. 15, 


1871. 


E. Fitzhenry, 


Boston, Mass. 


119,513 


Oct. 3, 


1871. 


E. Fitzhenry, 


Boston, Mass. 



' For other forms of scouring machines, see those combined with unhairing 
machines in list on page 333. 



408 



THE MANUFACTURE OF LEATHER. 



No. 


D 


ate. 




Inveutoi'. 


Residence. 


125,276 
129,251 
131,831 


April 
July 
Oct. 


2, 

16, 

1, 


1872. 
1872. 
1872. 


E. Fitzlienry, 
A. W. Reid, 

N. F. Snow, 


Somerville, Mass. 
Schenectady, N. Y 
Salem, Mass. 


143,829 


Oct. 


21, 


1873. 


F. A. Lockwood, 


Boston, Mass. 


151,144 
154,249 


May 
Aug. 


19, 

18, 


1874. 
1874. 


J. Maxwell, 
J. Head, 


Woburn, Mass. 
Andover, N. Y. 


156,991 


Nov. 


17, 


1874. 


E. Fitzlienry, 


Somerville, Mass. 


157,691 


Dec. 


15, 


1874. 


F. A. Lockwood, 


Boston, Mass. 


173,627 


Feb. 


15, 


1876. 


J. Head, 


Andover, N. Y. 


176,216 


April 18, 


1876. 


H. D. Chemberlin 


Berlin, Wis. 










and J. P. Luther, 




179,928 


July 


19, 


1876. 


F. A. Lockwood, 


Boston, Mass. 


180,018 
193,615 
194,806 
196,793 


July 
July 

Sept. 
Nov. 


18, 

31, 

4, 

6, 


1876. 

1877. 
1877. 
1877. 


E. Fitzhenry, 
W. Panton. 
T. L. Daheney, 
C. T. Ford, and 


Somerville, Mass. 
Quincy, 111. 
Stoneham, Mass. 
Salem, Mass. 


235,131 ^ 
Reissue > 
9,824* 
238,589 


Dec. 

Aug. 

Mar. 


20, 

2, 

8, 


1880. } 
1881. ^ 

1881. 


S. A. Ford, 
J. W. Cubbage, 
C. Holmes, 


Gallipolis, 0. 
Boston, Mass. 


240,997 
252,369 


May 
Jan. 


3, 
17, 


1881. 

1882. 


W. Goodman, 
W. Goodman, 


Boston, Mass. 
Boston, Mass. 


258,659 


May 


30, 


1882. 


F. A. Lockwood, 


Boston, Mass. 


260,492 


July 


4, 


1882. 


J. C. Mayer, 


Somerville, Mass. 



CHAPTER XXII. 

STUFFING LEATHER — HAND STUFFING AND STUFFING WHEELS — 
STUFFING AND CURRYING COMPOUNDS — MACHINE FOR REMOV- 
ING GREASE FROM LEATHER — LIST OF AMERICAN PATENTS FOR 
STUFFING APPARATUSES AND FOR STUFFING AND CURRYING 

. COMPOUNDS. 



Section I. Hand Stuffing and Stuffing Wheels. 

In the manufacture of upper leather, after the sides have been 
scoured as described in the preceding chapter, thev are exposed 
to the air to harden and are next carried to the cellar of the 
shop to be dampened and tempered, so as to facilitate the absorp- 



STUFFING LEATHER. 409 

tion of the grease ; the tempering process generally extending 
through two days. 

The period of tempering depends upon whether the leather is 
to be stuffed by hand or machinery. When stuffed by hand the 
leather requires to be damper than when stuffed by means of 
the wheel. 

Ordinarily the hand process of stuffing leather is accomplished 
after rolling the sides into bundles with the grain side in and 
softening them by treating or beating, and then applying to the 
flesh side by means of a brush, a mixture of oil and tallow in a 
heated state. In addition to the trouble and expense of the 
hand method of stuffing another objection arises from the fact 
that the leather has to be dampened to such an extent that it 
necessitates a long period for drj^ing, and then again, after the 
partial absorption of the oleaginous and fatty materials the sur- 
face of the leather has to be separately cleaned of the unabsorbed 
matter. 

Another great objection to the hand method of stuffing leather 
is that the stuffing materials, unless great care is observed, pene- 
trate only slightly beyond the surface, thereby leaving the 
leather, as regards the main body, dry and unchanged, and con- 
sequently hard. But when the modern stuffing wheel is used 
for this purpose the leather is usually thoroughly permeated 
and thereby rendered soft and pliable. 

Stuffing Wheels. 

The first stuffing wheel patented in this country was invented 
by L. W. Fiske, of Louisville, Ky., early in 1855, although pre- 
vious to this time they had been used in France and Grermany 
in the crude form of a revolving hogshead. 

But those which are now in use in the United States are of 
permanent construction, and show the usual evidence of mechan- 
ical ingenuity for which American inventors are pre-eminent. 

Reed and Winchester'' s Stuffing Wheel. 

The stuf&ng wheel shown in Figs. 160 and 161 is the inven- 
tion of Reed and Winchester. 

This invention in stuffing leather has for its object a method. 



410 THE MANUFACTUEE OF LEATHER, 

wlierebj the grease may be put into the leather more regularly 
than heretofore. The leather must be warm, and be kept warm 
uniformly during the time the grease is being applied to it. 

The leather to receive grease or stuffing is usually placed in 
"a rotating drum or wheel previously heated by steam or hot air 
blown into it while the wheel is empty, for it has been found 
that steam injected into the drum in the presence of the leather 
is apt to burn it. A drum heated only before placing the leather 
in it commences to cool immediately thereafter, and the stuffing 
or greasing operation is retarded. Another serious objection to 
the direct introduction of steam into the drum with the leather 
and grease is that arising from water of condensation, as even a 
small amount of water added at that time, the leather having 
been evenly and sufficiently moistened before it was placed in 
the drum, will be taken up by the leather, thus lessening the 
amount of grease entering the leather at that spot where the 
water of condensation in the grease meets the leather, and, 
further, the heat derived from free steam varies materially, 
according to the pressure of steam in the boiler. To obviate 
the objection of free steam the drum has been placed in a second 
drum heated by steam. 

In this invention the interior of the drum and leather therein 
are kept at the desired temperature by means of heated air 
forced therein while the drum containing its charge of leather 
is being rotated. The hot air is supplied to the drum by a 
blower or pump through pipes, in connection with a receiving- 
chamber of a suitable heat-generating apparatus. 

Figure 160 represents, in vertical section, an apparatus 
embodying Reed and "Winchester's invention, the wall of the 
heat-generating apparatus being also in section. Fig. 161 is an 
elevation of the left-hand end of the drum, the latter being 
partially broken out. 

The drum a, about seven feet in diameter, has a door, h, for 
the introduction of the leather therein, and a series of pegs, c, 
at suitable intervals apart to lift and tumble the leather as the 
drum is rotated, all as usual. This drum has at one journal a 
pipe, d^ for the introduction at suitable times of hot grease, and 
at its other journal it has a pipe, e, for the continuous admission 



STUFFING LEATHER. 



411 



of hot air while the drum is being rotated with the leather and 
grease therein. The pipe e is preferably placed, in coil or other 
form, in the combustion-chamber/, heated in any usual way, 
so that air forced through the pipe by an air-forcing apparatus. 




Fig. 161. 




g (shown as a blower, but which might be a pump), will be 
heated before reaching the drum. The side of the drum will 
be provided with openings of suitable size for the escape of the 
heated air, so as to maintain proper circulation. The air so 
escaping might be delivered into an annular chamber, /i, placed 



412 THE MANUFACTURE OF LEATHEE. 

next to the openings of the wheel (see Fig. 160), having a pipe, 
«', to lead the air out of the building, if desired. 

The air-pipe, at a point between the chamber / and drum, 
may have a branch, Jc, by which, if desired, to divert the heated 
air into a water- box and over a pan of water, to thus add a 
little moisture to the hot air, if too dry ; or we may inject a 
small amount of steam into the pipe e containing the hot air, to 
slightly moisten it, care being taken to so regulate the steam 
that no water of condensation is permitted to form or enter the 
drum. 

In this process it is possible to keep the interior of the drum 
and the leather therein at a uniform temperature, which may be 
indicated by a thermometer properly connected with the drum 
which enables the leather to be greased or stuffed uniformly 
and rapidly, and thatwitliout fear of injuring the leather in any 
way by over-heating, as when steam is depended upon, or by 
too rapid cooling, as when the drum is heated only before ap- 
plying the leather. The grease, in proper quantities, can be 
introduced from time to time, as needed. 

This valuable invention appears to have been suggested by 
that of Dr. Friederich Knapp of Brunswick, Germany, who in- 
vented an improvement in tramping-drums in 1878, which pos- 
sessed the combination of the drum and hollow trunnions and 
the blower or fan and other arrangements very similar to the 
stuffing wheel which has just been described; but while our 
Government granted Knapp a patent for the fan attachment 
to the stuffing wheel the German Government had previously 
refused it as not being a new idea. 

Frederick CarVs Improved Stuffing Wheel. 

The stuffing wheel shown in Figs, 162 and 163 is the inven- 
tion of Frederick Carl, and is an improvement upon the machine 
patented by him in 1867. 

Figure 162 is an isometrical perspective view, and Fig. 163 a 
vertical longitudinal section of Carl's improved stuffing Avheel- 

A represents the body or cylinder of the machine, which is 
journaled at B in the supporting- frame C, and provided with 
an opening, D, for inserting the leather. A steam-supply pipe, 



STUFFING LEATHER. 



•il3 



E, passes through one of the journals B, with which it revolves, 
and thence at right angles upwardly along the outer side of one 
end of the body A, as seen at F^ terminating in the branches d 
d\ for conveying steam to the twin or corresponding heater dis- 
posed within the cylinder, of which the heater is shown at G in 
Fig. 163. 

Fig. 162. 




The heater consists of a continuous pipe, or pipe without 
joints, bent to form parallel sections a a, and curved laterally to 
conform to the interior curvature of the cylinder, a drain-pipe 
or stopcock, H, being provided to draw off the water of con- 
densation. 

A series of slats or bars, J tl, provided with pins 7n m for 
catching and holding the leather, are secured longitiidinally 



414 THE MANUFACTURE OF LEATHER. 

within the cylinder, the heaters being disposed between said 
bars and the outer casing of the body A. There is also a screen 
or wire-netting, K (shown as partially removed in Fig. 163), 
attached to the bars J" J, the pins mm projecting inwardly 
through the netting when the same is in position. The netting 
forms the interior side walls of the cylinder, its object being to 
eftectually prevent the leather from coming into actual contact 
with the pipes without preventing the heater from properly 
acting on the stuffing or leather contained in the cylinder. . 

In the use of this stuffing wheel, steam having first been let 
into the apparatus through the pipe E^ the leather and compo- 
sition for stuffing the same are inserted in the body A through 
the opening i), which is then secui'ely closed, and the cylinder 
caused to rotate by any suitable means, thus rapidly and effec- 
tually performing the operation of stuffing in a manner which 
will be readily understood by all conversant with such matters 
without a more explicit description. 

The wheel may be made to revolve either by suitable gear- 
wheels or a belt may be passed from a pulley on a revolving- 
shaft around the cylinder A. 

List of Patents for all Apparatuses for Stvjffiyig and Greasing Leather^ 
issued by the Government of the United States of America, from 
1790 to 1883 inclusive. 

Inventor. Residence. 

L. W. Fiske, Louisville, Ky. 

G. Huttelmaier, Allegheny, Pa. 

F. Carl, Charlestown, Mass. 

H. Muller, North Cambridge, Mass. 

J. W. Schayer, Boston, Mass. 

H. Smith, Jr., Milwaukee. Wis. 

W. A. Perkins, and Salem, Mass. 

J. A. Enos, Peabody, Mass. 

J. A. Enos, Peabody, Mass. 

Gr. H. Williams, Milwaukee, Wis. 

J. A. J. Shultz, St. Louis, Mo. 

J. W. Hildreth, Boston, Mass. 

N. H. Dodge, Brooklyn, N. Y. 

,J. A. J. Shultz, St. Louis, Mo. 

H. P. Reed, and P. Peabody, Mass. 

L. Winchester, Jr. 

F. Carl, Somerville, Mass. 



No. 


Date. 


1855. 


40,079 


Sept. 22, 


1863. 


63,856 


April 16, 


1867. 


78,<S15 


June 9, 


1868. 


78,835 


June 9, 


1868. 


100,939 


Mar. 15, 


1870. 


131,777 


Oct. 1, 


1872. 


147,379 


Feb. 10, 


1874. 


153,654 


July 28, 


1874. 


177,576 


May 16, 


1876. 


201,526 


Mar. 19, 


1878. 


219,233 


Sept. 2, 


1879. 


245,321 


Aug. 9, 


1881. 


245,975 


Aug. 23, 


1881. 


249,455 


Nov. 15, 


1881. 



STUFFING LEATHEB. 



415 



Section II. Stuffing Compounds. 



Andreivs^s Compound. 

In 1869 Kobert Andrews improved upon a method patented 
by him in 1867, for preparing a composition for stuffing leather, 
and for all purposes in which grease, oils, or tallow are used in 
manufacturing leather. 

This method consists of combining, mixing, and compound- 
ing common or crude tar with tallow, beeswax, linseed oil, 
neat's-foot oil, and the oil of tar, in such proportions, and in 
such a way and manner as to cause the particles of each to 
assimilate and form a composition to be used principally in the 
manufacture of leather, and chiefly for " stuffing." 

The method of making this composition embraces simply the 
process of eft'ecting a combination of the tar, tallow, and oils. 
Ordinarily, common or crude tar will not unite with tallow and 
oil. 

But Andrews claims to effect this process as follows : Put 
together into a large caldron or iron vessel a quantity of tallow, 
oil of tar, beeswax, linseed oil, and neat's-foot oil, in such quan- 
tity of each as is proper, chiefly in the following proportions 
and quantities : 

Linseed oil . , . . . .1 gallon . 

Neat's-foot oil .- . . . . 1 gallon 

Oil of tar ...... \ pound 

Tallow ...... 10 pounds 

Beeswax ...... 1 pound 

and heat them over a slow fire until they boil or attain the 
highest degree of heat without igniting. Then take of this 
boiling mixture small quantities at a time, in a scoop- or dipper, 
and pour it carefully into the vessel containing the crude or 
common tar which has been prepared for compounding. While 
the heated oils are thus being gradually introduced into the tar,. 
cause it to be agitated and moved by stirring it with some in- 
strument. After the tar becomes warmed and softened, quickly 
and at once pour the whole of the remainder of the boiling oils 
which has previously been made ready for the purpose, and 



416 THE MANUFACTUEE OF LEATHER. 

mix the entire mass thoroughly until there is a complete min- 
gling of the whole. Before the mixture cools, again put it into 
an iron caldron and subject it to a slowly increasing heat until 
it boils, being careful to avoid ignition. Then draw the liquid 
ofi' into a vessel and let it stand until it becomes cold, when it is 
ready for use. 

Stufl&ng compounds of this character impart great consistency 
to fats, and such combinations as that which has just been given 
insure a good purpose, the only objection being that leathers 
so treated are liable after a time to become dry and stiff". 

MerrilVs Compound. 

In 1870 Joshua Merrill patented a stuffing compound, com- 
posed of solid paraffine mixed with tallow, fish oil, rosin, rosin 
oil, and tar of commerce, or either of them. 

Paraf&ne, having no tendency to absorb oxygen, acts as an 
antiseptic, preventing the oxidation of such substances as those 
above mentioned, and like substances, thereby preventing them 
from drying or hardening in the pores of the leather. 

By "solid paraffine," is meant either the article known in the 
market as " scale paraffine," or that known as refined paraffine. 

A compound composed of thirty-three parts paraffine, thirty- 
three parts rosin, twenty-four parts rosin oil, and ten parts ren- 
dered tallow, makes a stuffing or dressing for leather of great 
value, finishing goat and sheep-skins it is claimed so that they 
resemble calf-skins. It renders them soft and pliable, and they 
finish with a beautiful surface. 

This compound, it is also claimed, finishes calf-skins equal to 
good French calf, and at comparatively small cost, as compared 
with the high-priced oils usually employed for dressing the 
kinds of finer leather. 

A. composition of thirty-three parts paraffine, thirty-three 
parts rosin, fourteen parts rosin oil, ten parts North Carolina 
tar or tar of commerce, and ten parts of tallow or fish oil, also 
makes a good compound for stuffing leather. 

In manufacturing this paraffine stuffing compound, use a ket- 
tle heated by fire directly applied, or by steam heat (by means 
of a double-walled kettle), such as usually employed in melting 



STUFFING LEATHER. 417 

glue, into which first put the parafBne, then the rosin oil and 
tallow or fish oil, with the tar, when used, and heat them until 
thoroughly melted and heated to about 220° F. Then allow it 
to rest until it is clear and bright, when it is ready for use, if 
the operation has been properly conducted. 

The parafiine stuffing compound thus made will be clear and 
bright, and when rubbed between the fingers will be soft and 
unctuous like a thick fatty matter. When cold, it is of the 
consistency of very solid greasy matter. 

It is not always necessary to be confined to the exact propor- 
tions of parafiine, rosin, rosin oil, and tallow, or fish oil above 
given, for the proportions may be varied considerably with good 
results. 

In some cases the inventor uses as much as fifty parts rosin, 
but it has been found that a less proportion than twenty-five 
per cent., by weight, of parafiine is not so reliable and valuable 
as a stuffing compound, as it loses its antiseptic power in a con- 
siderable degree, when mixed less than twenty-five per cent. 

Leather stuffed with this compound, it is claimed, remains 
soft and pliable for a long time. 

Williams's Compound. 

Dr. Theodore D. Williams in 1870 patented a compound for 
stuffing and finishing leather which consists in combining neat's- 
foot, bank, straits, olive, fish, or horse oil with glycerine and 
tallow, by and through the presence of " glycerole" of egg, in 
quantities in accordance with the following specifications, and 
permitting the combining, of an additional quantity Of either of 
the aforesaid ingredients, for the purpose of adding to or re- 
ducing its common density, without dissimilating or degene- 
rating its original and perfect chemical union. The complete 
union of these ingredients is dependent upon the " glycerole" 
of egg, which substantiates Williams's improvement, and thus 
brings these animal oils and fats into a perfect homogeneous 
mass or assemblage. 

" Glycerole" of egg is prepared by adding together five parts 
of egg (white and yolk) and four parts of glycerine. 

The following are the constituents and the respective quanti- 
27 



418 THE MANUFACTURE OF LEATHER. 

ties of this curriers' stuffing and finish, together with manner 
of putting them together : First, mix " glycerole" of egg, three 
parts ; glycerine, five parts ; second, mix neat's-foot oil, four 
parts ; tallow (consistency of the oil), two parts. While the oil 
is warm (not hot) stir in the No. 1, and continue to stir until 
quite cold and stiff. 

Dr. Williams claims that this constituent, " glycerole" of egg, 
is that which induces the perfect chemical union of the several 
ingredients by its afl&nity for both the oils and fats, and therein 
its power of suspension of same ; he also claims that, to a great 
extent, it prevents the loss of oils and fats, which are carried 
into the leather by its presence and power of assimilating, while 
being subjected to the process of crimping, treeing, etc., in the 
manufacturing of leather into boots and shoes; and, further- 
more, by its power of retaining large proportions of these oils 
and fats, it thereby remains soft and pliable, and that it is in no 
manner injurious to the leather. 

Thayer'' s Compound. 

This compound, which was patented by Mr. Edward S. Thayer 
of Salem, Mass., in 1878, is intended more particularly for stuff- 
ings, but is also adapted to other uses in treating leather. 

It consists in an admixture of paraffine-wax and what is 
known in the United States market as "degras," the same con- 
sisting of the product proceeding from the treatment of the 
waters coming from the wool factories by chemical process, the 
same containing the " suint" extracted from the wool, and the 
greasy and oily matters from the soaps and oils used in those 
factories. This compound of paraffine-wax and degras may be 
used either alone for the purpose, being effective singly, or it 
may be used in combination with tallow or other suitable mate- 
rials. 

The proportions of the parafi&ne-wax and degras may be 
varied as necessity may require, but for ordinary wheel-stuffing 
the following is preferable : Paraffine-wax, one hundred pounds ; 
degras, two hundred pounds. The amount of tallow, if any, 
used with the above will be small, and may be graded as desired. 

The paraffine-wax serves as the body of the compound, to fill 



STUFFING- LEATHER. 419 

tlie pores and harden and give substance to the leather. The 
degras serves as a solvent to cut the wax and as a vehicle to 
convey the wax into the pores. It is very penetrating, and the 
whole forms a compound which is very efficient for the treat- 
ment of leather. 

The leather produced is of a superior quality, does not turn 
white or gummy, and will retain for a long time its original 
softness. If the finished stock is too hard, more of the degras 
must be used ; if too soft, less. 

The compound can be used advantageously as a wheel-stuffing, 
or as an ordinary hand-stuffing, or for the treatment of finished 
leather. This product (degras) is well known commercially in 
the United States under the name designated, and is to be dis- 
tinguished from a material of the same name known in Germany 
and France, which consists of the residue or product proceeding 
from the tanning of buck, goat, or sheepskins, treated by alkali 
to remove the oily and gelatinous matters, and which oily and 
gelatinous matters, together with alkali and water, form what is 
known there commercially as "degras," and which is described 
more fully in the chapter of this work devoted to the manufac- 
ture of glove-leathers. 

" -S. S. OiV for Stuffing Compounds. 

Dewees and Green patented the following process by which 
it is claimed that leather may be rendered nearly impervious to 
water and left in a soft condition by use of the following cheap 
stuffing compound : Take B. S. oil, which is a residuum found 
in oil-tanks after the oil has been drawn off, and which is hea- 
vier than oil, and of different consistency at different wells or 
tanks. 

This oil is well known in the American market as " B. S. 
Oil." Of this oil take a given quantity and set it on fire in the 
open air and let it burn until all the sulphur is consumed ; the 
residuum will be a pure carbonaceous material. 

The time required for this burning varies with the kind of 
oil ; but the process is usually considered complete when 1 gal- 
lon of the oil thus heated weighs about 7 pounds and 7 ounces. 

After the oil has been thus treated there is added, to each 1 



420 



THE MANUFACTURE OF LEATHER. 



gallon of the refined oil, 7 pounds of tallow. These proportions 
may be varied to adapt the stuffing compound to thin and thick 
leather, and to different temperatures. 

List of all Patents for Compounds for Sttiffing Leather, issued by the 
Government of the United States of America, from 1790 to 1883 in- 
clusive. 



No. 


Date 




12,368 


Feb. 


6, 


1855. 


14,832 


May 


6, 


1856. 


15,499 


Aug. 


5, 


1856. 


44,025 


Aug. 


30, 


1864. 


54,587 


May 


8, 


1866. 


55,426 


June 


5, 


1866. 


55,715 


July 


19, 


1866. 


57,165 


Aug. 


14, 


1866. 


61,379 


Jan. 


22, 


1867. 


90,333 


May 


25, 


1869. 


100,652 


Mar. 


8, 


1870. 


107,579 


Sept. 


20, 


1870. 


160,440 


Mar. 


2, 


1875. 


204,398 


May 


28, 


1878. 


209,800 


Nov. 


12, 


, 1878. 



Inventor. 
L. W. Fiske, 
J. Rose, 
F. A. White, 
A. Taw, 
M. W. Page, 
C. L. Morehouse, 
J. A. Roth, 
T. McDonald, 
R. Andrews, 
R. Andrews, 
J. Merrill, 
T. D. Williams, 
H. Klemm and 

C. Klemm, 
E. S. Thayer, 
M. L. Dewees and 

W. W. Green, 



Eesldence. 
Louisville, Ky. 
Newark, N. J. 
Roxbury, Mass. 
Philadelphia, Pa. 
Franklin, N. H. 
Cleveland, Ohio. 

Philadelphia, Pa. 

Roxbury, Mass. 

Milwaukee, Wis. 

Milwaukee, Wis. 

Boston, Mass. 

Chicago, 111. 

PfuUingen, Germany. 

Salem, Mass. 
Elk City, Pa. 
Cambridgeborough, Pa. 



List of all Patents for Compounds for Currying^ Leather, issued by the 
Government of the United States of America, from 1790 to 1883 in- 
clusive. 

Inventor. Eesidence. 

A. Hickman and Abingdon, Va. 

E. L. Davenport, 

M. W. Page, Franklin, N. H. 

A. Doepp, Newark, N. J. 

Wm. Kinsey, Cincinnati, 0. 

J. H. Radey, Philadelphia Pa. 

R. Hart, Gloversville; N. Y. 

J. Carmody, New York, N. Y. 

P. Ware, Jr., Boston, Mass. 

E. F. Dietsrich, Philadelphia, Pa. 

J. Kent, Gloversvill-e, N. Y. 

N. Quinland and Glens Falls, N. Y. 

J. H. Quinland, Jr., 

E.W.Phillips, Waverly,'N. Y. 

M. B. Tice, Newark, N.. J. 



No. . 


Date. 




866 


Aug. 


1, 


1838. 


54,587 


May 


8, 


1866. 


84,096 


Nov. 


17, 


1868. 


147,847 


Feb. 


24, 


1874. 


160,841 


Mar. 


16, 


1875. 


160,902 


Mar. 


16, 


1875. 


161,203 


Mar. 


23, 


1879. 


167,142 


Aug. 


24, 


1875. 


171,719 


Jan. 


4, 


1876. 


182,368 


Sept. 


,19, 


1876. 


203,498 


May 


7, 


1873. 


222,944 


Dec. 


23, 


, 1879. 


225,772 


Mar. 


23, 


1880. 



1 See also list of compounds for stuffing leather. 



STUFFING LEATHEE. 



421 



Section III. Machine foe Removing Gteease feom Leathee. 

The machine for removing grease from leather, which was 
invented in 1872 by William A. Perkins, of Salem, Mass., is 
shown in Fig, 164, and is an improvement on the machine, for 
this purpose patented by J. T. Barnstead in 1870, in which a 
knife is made to reciprocate over a suitable bed, and a brush is 




used to remove the grease which is attached to the knife at each 
reciprocation. This brush is found in some cases to be inopera- 
tive and liable to objections which Perkins's invention is 
designed to remove. It is important that the knife which 
scrapes the grease from the leather should be properly cleaned 
at each stroke, or the accumulation of grease on the- knife is 



422 THE MANUFACTURE OF LEATHER. 

liable to drop on the leather and soil it. To accomplish this 
result Perkins uses in place of the brush in Barnstead's machine 
a metal plate, which may be mounted in the same manner as in 
Barnstead's machine ; but the arrangement shown in Fig. 164 
and described is preferable. 

Fig. 164 shows a vertical section of Perkins's Machine. 

A represents the frame of the machine ; B, the adjustable 
bed ; C, the pendulum-arm, to which is attached the knife D. 
The pendulum-arm is made in two parts and jointed at ^ so 
that the knife is raised clear of the leather at the return stroke. 
Motion is communicated to the pendulum through the connect- 
ing-rod F. On the back side of the frame A is bolted a curved 
spring, G, which is made preferably of steel. To this spring is 
attached the scraper IT, in the position shown. The scraper H 
is made of a thin narrow plate of steel or iron. 

At each reciprocation of the knife D over the leather a 
quantity of grease is removed, which attachesitself to the knife. 
As the knife passes over the bed it leaves the leather and comes 
in contact with the scraper 11, which removes the grease from 
the knife, and it drops into a receptacle placed for the purpose 
clear of the frame A. 

Fig. 164 shows the knife and scraper in the position just 
described. 

The distance of the scraper U from the knife is adjusted by 
means of the screw /. 

List of all Patents for Machines for Removing Grease from Leather, 
issued by the Government of the United States of America, from 1790 
to 1883 inclusive. 



No. 




Date 




Inveutor. 


Residence. 


101,081 \ 


Mar. 


22, 


1870. "i 






Reissue > 






\ 


J. T. r.arnstead, 


Peabody, Mass. 


4,258) 


Feb. 


14, 


1871.) 


. 




105,506 


July 


19, 


1870. 


J. Starratt, 


Salem, Mass. 


122,130 


Dec. 


26, 


1871. 


J. Perkins and 
Gr. L. Newcomb, 


Peabody, Mass. 


123,643 


Feb. 


13, 


1872. 


W. A. Perkins, 


Salem, Mass. 


252,559 


Jan. 


17, 


1882. 


E. V. Wliitaker 
and J. Hull, 


Gloversville, N. Y. 



WHITENING LEATHER. 



423 



CHAPTER XXIII 



Whitening- Leather. 



next " set out" (which 
for calf-skins or the 



Fig. 165. 




The side having been stuffed and 
latter operation can be performed 
heavier grades of upper leather by 
the Lockwood machine shown in 
Figs. 138 to 140, or the Fitzhenry 
machine shown in Figs. 147 to 151), 
the next step in the process of manu- 
facturing upper leather is that of 
whitening. This is usually accom- 
plished by one of three ways: The 
leather may be placed on a table and 
whitened with a slicker, or cut 

over with a currier's knife or a beam, or the whitening can be 
performed by machinery. 

Fig, 165 shows the French pattern of whitening slicker, which 
is the kind usually employed in this country. The blades, 
which are of cast steel, are usually of two degrees of hardness ; 
the bright blade compares in temper with a medium hard blade, 
the half polished are softer, being of a lower temper. 

Fig. 166 shows the form of beam now generally employed in 
currying shops. The beam-bed and face are adjustable by 
means of screws, and the beam may be elevated or lowered at 
any necessary height to suit the convenience and comfort of the 
workman. The faces may be either of lignum vitge or of glass. 

There is a great variety in the construction of currier's 
knives; but the form shown in Fig. 167 is the most common. 
The blades are screwed in the brass jaws by three screws from 
each side, thus securing equal strength. The blades for the 
currier's knives are made from hammered steel, and are either 



424 



THE MANUFACTURE OF LEATHER. 



bright or unpolished, and vary from seven-eighths to two inches 
in width, and those kept in stock bj the manufacturers are 



Tis. 166. 




Fig. 167. 




made in nineteen and twenty gauge ; but other gauges are 
manufactured to order. 

Clements' s Leather- Whitening Machine. 

The leather-whitening machine shown in Figs. 168 to 172 is 
the invention of John E. Clements, and it is an improvement on 
the leather whitener patented by Enos and Clements in 1881. 

Fig. 168 is a plan view of the machine. Fig, 169 is an end 



WHITENIKG LEATHER. 



425 



view. Fig. 170 is a cross-section on line x x of Figs. 168 and 
171. Fig. 171 is a longitudinal section on line y y ol Fig. 168, 
and Fig. 172 is a detail section of the thrust-box. 



Fiff. 16 




Fig. 169. 




A is the bed-plate, i? is a stand supporting the rocking hub 
G by its spindle a. Z) is a stand carrying feed-bed E. h h are 
stands supporting a horizontal shaft, ^, which carries fast and 



426 



THE MANUFACTURE OF LEATHER. 



loose pulleys h ¥ for the belt from the main driving-shaft and 
a pulley, Z, for a belt to drive an overhead counter-shaft. 



Fig. 170. 




-,^:,rr„,-r^^^\.:,jj\>.J.,\^^J'^jjAf^J'fJ'ffI^J!ZSZ± 



FicT. 171 




Fig. 172. 




h V are arms projecting from hub G. e is the cutter-shaft sus- 
tained in suitable bearings on the arm &', and carrying the cutter- 
head/ above bed E, and also provided with a pulley,, g. 

i^ is a stand supporting a horizontal slide-way, m, at the end 



WHITENING LEATHER. 427 

of arm 7;, and n is a slide-block fitted for movement on the 
slide v\^ay. 

is a wrist-pin on the slide-block, to which is connected a 
rod, p^ from a crank-wheel, §, on shaft i. 

T is a gudgeon attached to slide w by a pin, r', and fitting a 
slot, s, in the end of the arm h of the hub (7, so that by move- 
ment of the slide the hub is rocked, the movement of the gud- 
geon in slot /S', allowing for change of position. 

The grinder a' is an emery-wheel, bearing on the cutters at 
one side of the head, the intention being to have continuous 
contact which is regulated, as the grinder wears, \>y turning the 
screws u to force shaft %o downward. A worm-shaft, c' , carried 
by brackets t and engaging worm-wheels u' on the screws, is 
used for simultaneous movement of the screws. 

On the grinder shaft lo is a pulley, c?', connected thereto by a 
pin and key-slot, that allows endwise movement of the shaft. 
e' is a rod sustained in guides e^ on boxes v , and connected by a 
rod,/', to the crank-arm of a short cross-shaft, (j\ that is sus- 
tained on the rocking-arm h. The shaft g' is connected by a 
worm and pinion at h' with a shaft, ^', that extends to hub (7, 
where it has a pulley, /c', turned by contact with the driving- 
belt V of the cutter shaft, so that the rod eJ is given an endwise 
reciprocation. On the grinder-shaft is a thrust-box, m' (shown 
most clearly in Pig. 172), which has internal flanges taking into 
grooves on the shaft, and has also an apertured flange, n\ 
clamped on rod e' by a set-screw, whereby the grinder-shaft is 
reciprocated with the rod. By these devices the grinder is 
moved back and over the cutters from one side of the cutter- 
head to the other. The same movement may be obtained by 
connecting the outer end of reciprocating rod direct to grinder- 
flanges by means of a fork. In this case the grinder-shaft does 
not reciprocate, but same motion is communicated to grinder 
and flanges which reciprocate upon the end of shaft having 
spline, key, or feather set into it, giving the grinder a rotary 
movement. 

The cutter and grinder are driven by the belt V from the 
overhead counter-shaft, which, as before mentioned, is driven 
from the shaft ^. The belt V passes first beneath a tightening- 
pulley, o', that is hung on a bracket, p', then upward and over 



428 



THE MANUFACTURE OF LEATHER. 



the pulley d' of the grinder- shaft, and then beneath pulley g of 
the cutter-shaft, as shown most clearly in Fig. 170. The driv- 
ing-belt thus extends at right angles, or nearly so, to the plane 
in which the hub G rocks, and is slightly twisted by the rocking 
movement. That arrangement is more reliable, because the 
belt remains centred on the pulleys, and is not shifted from 
side to side, as is the case with a belt extending in the plane of 
vibration. The bracket ^' of the tightener-pulley o' is attached 
to hub G by screws passing through slots in the bracket, so that 
adjustment can be readily made. 

In place of the cutter-head, a smooth or fluted roller, hollow 
and heated by steam, may be substituted, and the machine then 
used for ironing and glossing leather. 

Smith'' s Leather- Whitening and Buffing Machine. 

The machine for whitening and buffing leather invented by 
Oliver C. Smith is shown in Figs. 173 to 176. 

Fig. 173. 




Fig. 174. 




WHITENING LEATHEK. 



429 



Fig. 175. 





Figure 173 represents, in top view, a machine embodying 
Smith's invention ; Fig. 174, a longitudi- 
nal vertical section thereof on the dotted 
line X X, the table or bed being shown in 
elevation. Fig. 175 is an enlarged detail, 
partially in section, showing the boxes of 
the sliding frame ; and Fig. 176, a section 
of Fig. 175 on the dotted line y y. 

In this invention the pulley A is fixed 
directly upon the crank-pin A, joining the 

two cranks i k, projected from shaft B. The weight of the 
pulley A is counterbalanced by the weights C, one on each 
crank. The belt u on this large fixed pulley A is extended 
over the pulley t on the shaft a^ at the upper end of the usual 
swinging frame, and rotates the said shaft, together with its 
pulleys 5, which by small belts r revolve the rotary cylinder or 
tool p in the usual manner as the link g, herein made double, 
reciprocates the carriage D on the guide-rods c. This carriage 
is composed of yokes 20, 21, connected by a bar, 22, the yokes 
having depending from them bearings a^ to receive the shaft a^, 
which turns in the said bearings. The boxes which run on the 
guide-rods c have Babbitt or other linings, E F. Upon the lin- 
ing F^ the inventor has placed an adjusting- wedge, G^ provided 
with one or more inclined teeth or wedging-surfaces, 9, and 
above the adjusting-wedge he has placed a cap, /, having at its 
under side one or more opposed teeth or inclines, 8. 



430 



THE MANUFACTUEE OF LEATHER. 



List of all Patents for Currier'' s Slickers, issued hy the Government of 
the United States of America, from 1790 to 1883 inclusive. 



No. 


Date. 




Inventor. 


Eesidence. 


20,098 


April 27, 


1858. 


H. H. Sultzbach, 


Marietta, Pa. 


52,491 


Feb. 6, 


1866. 


J. Hankey, 


North Cambridge, Mass, 


62,064 


Feb. 12, 


1867. 


D. Peters and 
J. W. Pauly, 


Keokuk, la. 


42,397 


April 19, 


1864. 


D. Peters and 
W. D. Wilson, 


Keokuk, la. 


L15,709 


June 6, 


1871. 


Gr. T. Collins, 


North Eastham, Mass. 


127,756 


June 11, 


1872. 


G. B. Fowle, 


Boston, Mass. 



List of all Patents for 
the United States 



Currier's Knives, issued hy the Government of 
of America, from 1790 to 1883 inclusive. 



No. 
20,911 
28,594 
37,285 
51,942 
94,197 
111,901 
137,671 

149,563 
193,806 

208,593 



Date. 
July 13, 1858. 
June 5, 1860. 
Jan. 6, 1863. 
Jan. 9, 1866. 
Aug. 31, 1869. 
Feb. 21, 1871. 
April 8, 1873. 

April 14, 1874. 
Aug. 7, 1877. 
Oct. 1, 1878. 



227,597 May 11, 1880. 



Inventor. 
J. B. Wentworth, 
W. P. Moses, 
G. Featherston, 
J. P. Hawks, 
L. A. Gignac, 
J. T. Barnstead, 
C. A. Gardner and 

J. A. Enos, 
A. H. Beschormann, 
R. E. Cherington, 
T. Hansen and 

G. H. Weifenbach, 
J. Tuggle, 



Residence. 
Lynn, Mass. 
Exeter, N. H. 
Ausable Forks, N. Y. 
Troy, N. Y. 
Troy, N. Y. 
Peabody, Mass. 
Peabody, Mass. 

San Francisco, Cal. 
Holyoke, Mass. 
Racine, Wis. 

New Middleton, Tenn. 



Machines for Sharpening Currier's Knives. 

No. Date. Inventor. Eesidence. 

1,064 Jan. 8, 1839. W. Eagleston, Troy, N. Y. 

List of all Patents for Machines for Whitening, Buffing, and Shaving 
Leather, issued by the Government of the United States of America, 
from 1790 to 1883 inclusive. 



No. 
732 
26,641 


Date, 
May 10, 
June 5, 


1838. 
1860. 


S. 
J. 


Inventor. 
Graham, 
Turner, 


Residence. 
Roxbury, Mass. 
Cambridgeport, Mass, 


63,191 


Mar. 26, 


1867. 


T. 


F. Weston, 


Salem, Mass. 


65,919 


June 18, 


1867. 


C. 


Korn, 


Wurtsborough, N. Y. 


77,025 
85,030 


April 21, 
Dec. 15, 


1868. 
1868. 


L. 
C. 


B. Fox, 
Schmitz, 


Williamsport, Pa. 
Philadelphia, Pa. 


89,789^ 

Reissue > 

4,534 5 


May 4, 
Aug. 29, 


1869. 
1871. 


A, 


, W. Pratt, 


Salem, Mass. 



BOAEDING AND GRAINING BY MACHINERY. 



431 



No. 


Date. 




Inventor. 


Residence. 


138,874 


May 13, 


1873. 


J. A. Enos, 


Peabody, Mass, 


150,285 


April 28, 


1874. 


J. M'. Caller, 


Salem, Mass. 


157,442 


Dec. 8, 


1874. 


J. E. Fisk, 


Salem, Mass. 


157,939 


Dec. 22, 


1874. 


0. C. Smith, 


Ipswich, Mass. 


191,173 


May 22, 


1877. 


W. A. Perkins, 


Salem, Mass. 


191,400 


May 29, 


1877. 


J. G. Buzzell, 


Lynn, Mass. 


202,226 


April 9, 


1878. 


J. G. Buzzell, 


Lynn, Mass. 


247,014 


Sept. 13, 


1881. 


J. E. Clement and 
J. A. Enos, 


Peabody, Mass, 


248,290 


Oct. 18, 


1881. 


P. De Chamberet, 


Paris, France. 


248,518 


Oct. 18, 


1881. 


0. C. Smith, 


Ipswich, Mass. 


252,928 


Jan. 31, 


1882. 


J. G. Buzzell, 


Lynn, Mass. 


259,497 


June 13, 


1882. 


J. E. Clement, 


Peabody, Mass 


261,309 


July 18, 


1882. 


J. E. Clement, 


Peabody, Mass 



CHAPTEE XXIV. 



BOARDING AND GRAINING BY MACHINERY. 



Following the whitening the next step in the production of 
upper leather is that of " stoning out," and while this is some- 
times done by hand, it is almost generally accomplished by 
machinery, which is usually a "jack," very similar in many 
points of construction to the machines used for polishing and 
pebbling leather. 

If after " stoning out" the leather should require softening it 
is "boarded," and when this is done by hand it is a tedious and 
laborious operation ; but in this as in other branches of leather 
manufacture machinery has come to the aid of the workman, 
and now the softening and graining can be accomplished most 
satisfactorily, and at the expenditure of but little power, and 
with but little effort on the part of the operator compared to 
the old way. 

Before the introduction of boarding and graining machines, 
this portion of the finishing suffered its full share from the 
neglect or incompetence of the workman, and manufacturers 
were compelled to sell their leather at considerably less' per foot 



432 THE MANUFACTUEE OF LEATHER. 

than thej might have done with this department well looked 
after. 

But now the upper leather when boarded and grained on the 
best of these machines has that peculiarly soft and velvety 
feeling which formerly distinguished imported stock, and which 
is now common in the leather made by us both for home con- 
sumption and for our export trade. The armboard in common 
use is shown in Fig. 243, and it continues to be emploj^ed 
principally for Morocco and other light leathers. 

Coogari's Boarding and Ora.ininy Machine. 

Fig. 177 shows a perspective view of Coogan's Machine for 
boarding and graining leather. 

The two rollers A and _S, Fig. 177, may be of cork or a com- 
position covering, which with proper usage will last for one 
year or more, and when worn they can be renewed at but a 
trifling expense when compared with cork rollers. The rollers 
are each about eight inches in diameter, and placed one above 
another, and run on iron shafts, set in a frame at either end, but 
so that the upper roller can be raised or lowered at pleasure and 
adjusted at any desired distance from the lower one and held 
permanently in position by means of. the screws F. 

The upper roller is about four and one-half feet long, but the 
lower one is somewhat longer, forming a table, and the frame in 
which the shafts of these cylinders revolve is about seven feet 
long. 

Opposite the top of the lower roller B^ extending its full 
length, and arranged so that by a slight pressure on the treadle 
D underneath, or b}'' pushing with the hand, it can be brought 
to bear directly in the centre between the two rollers, is a thin 
steel feed-plate G. 

The rollers revolve in the same direction, so that by placing 
the leather on the feed-board C, with one end or side just over 
the edge, and moving it against the revolving rollers, the upper 
roller carries it in, and the lower roller carries it out, turning it 
sharply under the edge of the plate, and almost instantaneously 
boarding a side or whole hide, the time required for the opera- 



BOARDING AND GRAINING BY MACHINERY. 



433 




28 



434: THE MANUFACTUEE OF LEATHER. 

tion being about one-tenth of that which would be required to 
perform the same work by hand. 

Soveyh Boarding and Graining Machine. 

Hovey's machine for boarding and graining is shown in Figs. 
178 to 182, and the invention consists essentially of a stationary 
concave bed having an elastic or yielding surface on its inside 
and a reciprocating worker movable on an axis, and provided 
with a yielding convex surface adapted to work within the 
concave bed, also of a revolving brush-roller located in bearings 
attached to the worker, a little in advance of the holding device 
which will be mentioned, for the purpose of properly laying 
and keeping the leather smooth and to prevent it from wrin- 
kling during the process of boarding or graining it. 

There is an automatic device for locking and holding the 
leather attached to the forward end of the worker until the 
boarding or graining is accomplished. The inventor also uses 
a self-acting reversing device for automatically reversing the 
motion of the reciprocating worker during the operation of the 
machine. The reciprocating worker is provided with an adjust- 
able pressure-regulating device, by means of which the surface 
of the worker may be adjusted more or less in or out, as may 
be required, for regulating the pressure on the leather between 
the worker and the concave bed, according to the thickness of 
the leather that is operated upon. The concave bed and its re- 
ciprocating worker are of a sufficient size to take in a whole 
side of leather at one time, so that the soft and thin parts of the 
side may receive the same relative pressure as the thick parts 
and thus grain the side equally all over. 

Figure 178 represents a front elevation of Hovey's machine. 
Fig. 179 represents an end elevation of the same, showing the 
worker in the act of drawing the leather into and laying it 
inside of the concave yielding bed. Fig. 180 represents an end 
view of the machine, showing the motion of the worker, as 
reversed, in the act of boarding or graining the leather. Fig. 

181 represents an end view, seen from X in Fig. 178 ; and Fig. 

182 represents a front elevation of the automatic reversing 
device for the reciprocating worker. 



BOARDING AND GRAINING BY MACHINERY. 



435 



In using the machine one end of the leather to be grained or 
boarded is inserted between the bars d and d', which are made 



Fig. 178. 




automatically to close upon each other and to hold the leather 
firmly between them, and the reciprocating worker then pro- 



Fig. 179. 




ceeds in the direction shown by the arrow in Fig. 181. The 
reciprocating worker continues in the same direction to draw 



436 



THE MANUFACTURE OF LEATHER. 



and lay the leather D within the concave bed in a manner as 
shown in Fig. 179, and continues in the direction shown bj 



Fis. 180. 




d ''^' 




BOAEDING AND GEAINING BY MACHINERY. 



437 



arrows in Fig. 179 until its projection 71 hits the projection on 
the belt-shipper, when the motion of the worker is reversed, as 
shown by arrow in Fig. 180, and causing the leather D to be 
grained or boarded by being doubled upon itself, and, as it were, 
rolled between the elastic concave bed b" and the elastic cover- 
Fig. 182. 




ing c* in a manner closely resembling the manner of graining or 
boarding by hand tools. The worker continues to move in the 
direction shown by arrow in Fig. 180 until the reciprocating 
worker has completed nearly a revolution around its axis, and 
until the projection w again comes in contact with the reversing- 
projection 0, when its motion is reversed to that shown by the 
arrow in Figs. 179 and 181, and during this motion of the 
worker the hinged foot c?® on the end of the arm or lever d" is 
brought in contact with the inward projection /', causing the 
holding device d d' to open to enable the finished leather to be 
taken away and a new side inserted, which is automatically 



438 



THE MANUFACTUEE OF LEATHER. 



clamped and beld firmly between the parts dd' as soon as the 
dog or tooth e comes in contact with the sliding rod /^. The 
hinged foot d^ will pass freely by the lever-projection/' when 
the worker is moved in the direction of the arrow shown in 
Fig. 180, and when the worker is in such motion the dog or 
tooth e will also pass freely by the inner end of the sliding 
rod / ^. 

In the drawings, a and a' represent the ends or frames of 
the machine, between which is secured the concave bed, com- 
posed of an outer concave metallic frame, ft, wood lining Z;', and 
yielding elastic surface Z/", made of cork. India-rubber, or 
similar elastic material ; 7:) represents the counterweight to the 
reciprocating worker. 

Machine for Boarding and Graining Morocco. 

The machine showii in Fig. 183 is for boarding and graining 
Morocco, and is an improvement made by G, "W. Baker, of 

Fig. 183. 




Wilmington, Del., on the machine invented by Owen Coogan, 
which is shown in Fig. 177. 

This machine will soften light leathers in a highly satisfactory 



BOARDING AND GRAINING BY MACHINERY. 439 

manner, the " bone" all being taken out, and the machine will 
also " spring up" the pebble grain of Morocco equally as well as 
hand work. 

The machine is simple in its construction and operation. 
Two rollers, twelve inches in diameter, covered with composi- 
tion, revolve in the same direction, and adhere firmly to the 
skin. 

The table is connected with the treadle-motion on which the 
skin is placed with the grain side down for softening, and put 
in with the shanks parallel with the steel blade fastened to the 
edge of the movable table. The operator, by a slight pressure 
of the foot, pushes the blade between the running rollers, the 
skin being carried around the edge of the plate by the rollers, 
the top one carrying it in, while the lower one carries it out. 
This operation bites the skins over the edge of the plate, giving 
the same breaking action as the cork-hand boarding, only that 
it takes one-half of the skin in, which runs rapidly through the 
machine ; it is then reversed and the other part run through. 
The softness depends entirely on the number of times it passes 
through the machine, but ordinarily, twice is sufficient. 

In graining, the skin is reversed ; instead of putting the grain 
side down, put it up. 

The machine runs slowly, about forty-five revolutions per 
minute, and requires a little less than one-half horse-power, 
does its work cheaply and well, and is worthy of the attention 
of the Morocco trade. 

List of all Patents for Machines for Boarding and Graining Leather^ 
issued hy the Government of the United States of America, from 1790 
to 1883 inclusive. 



No. 




Date, 




Inventor. 


Eesidence. 




Mar. 


25, 


1835. 


C. Bassett, 


Boston, Mass. 


14,211 


Feb. 


5, 


1856. 


J. B. Wentworth, 




15,807 


Sept. 


30, 


1856. 


J. Greeuleaf, 




48,971 


July 


25, 


1865. 


W. H. Moore, 


Salem, Mass. 


54,360 


May- 


1, 


1866. 


G. R. Joliiison, 


Wilmington, Del, 


54,821 


May 


15, 


1866. 


J. Parker, 


Woburn, Mass. 


62,514 


Feb. 


26, 


1867. 


J. E. Wiggin, 


Stoneliam, Mass. 


94,196 


Aug. 


31, 


1869. 


L. A. Gignac, 


Troy, N. Y. 


108,319 


Oct. 


13, 


1870. 


M. B. Bishop, 


Whitingham, Vt. 



440 



THE MANUFACTURE OF LEATHER. 



No. 


Date. 




Inventor. 


Eesideuce. 


110,944 


Jan. 10, 


1871. 


U. R. Williams and 
Wni. P. Martin, 


Salem, Mass. 


119,743 


Oct. 10, 


1871. 


0. Coogan, 


Pittsfield, Mass. 


126,105 ^ 


April 23, 


1872. 






Reissue > 






L. Townsend, 


Terra Haute, Ind. 


8,088) 


Feb. 19, 


1878. 






135,350 


Jan. 28, 


1873. 


N. 0. Lownsberry, 


Wilmington, Del. 


138,133 


April 22, 


1873. 


0. Coogan, 


Pittsfield, Mass. 


140,633 


July 8, 


1873. 


N. 0. Lownsberry, 


Wilmington, Del. 


157,632 


Dec. 8, 


1874. 


P. O'Brien, 


Boston, Mass. 


161,269 


Mar. 23, 


1875. 


A. W. Perrin, 


New York, N. Y. 


168,497 


Oct. 5, 


1875. 


H. Howson, 


Philadelphia, Pa. 


176,535 


April 25, 


1876. 


L. R. Jenkins, 


Philadelphia, Pa. 


202,414 


April 16, 


1878. 


W. Coupe, 


South Attleborough, Mass, 


218,908 


Aug. 26, 


1879. 


L. P. Mason, 


Salem, Mass. 


241,303 


May 10, 


1881. 


W. Coupe, 


South Attleborough, Mass, 


248,220 


Oct. 11, 


1881. 


A. Schray and 
A. Barentigam, 


New Albany, Ind. 


253,533 


Feb. 14, 


1882. 


J. H. Hovey, 


Woburn, Mass. 



CHAPTER XXY 



BLACKING LEATHER. 



Section I. Blacking and "Smutting" Appliances. 

The side of leather having passed through the previously 
described operations and been last boarded, is now in the state 
for blacking, and this is performed both by hand and machinery. 
It is thought by manufacturers that the hand process is pre- 
ferable for the heavy grades of upper leather ; but upon what 
ground it is not plain, as some of the machines constructed for 
this purpose are models of mechanism, and perform the work 
much more economically and thoroughly than is usually done 
by the hand process. 

Figs. 184 and 185 show the two forms of blacking brushes in 
common use, and they are made both soft and stiff" the best 
quality are extra copper-wired, and have all bristles. The 



BLACKING LEATHER. 



441 



oval form is always made with a strap ; but the round form 
have either handles or straps. Both brushes are made in first 



Fig. 184. 



Fig. 185. 




and second qualities ; but it is economy to purchase the best 
grade, as the extra wear more than compensates for the small 
difference in price. 

Batchdder's Leather Blacking^ Coloring^ and Dressing Machine. 

Figs. 186 to 195 show the leather blacking, coloring, and 
dressing machine patented by Batchelder. 

Fiff. 186. 




Figure 186 is a left-hand-side elevation of a machine embody- 
ing Batchelder's invention ; Fig. 187, a front view thereof, with 
the table n omitted ; Fig. 188, a longitudinal vertical section of 



44:2 



THE MANUFACTURE OF LEATHER. 



Fig. 187 ; Fig. 189, an enlarged detail to be referred to ; Fig. 
190, a detail in top view of Fig. 189, with the brush c omitted ; 
and Fig. 191 is a modification to which reference will be made. 



Fig. 187. 




The blacking or liquid dressing, or material to be applied to 
the upper surface of the hide or skin B, is placed in the recep- 




tacle e, which is shown as an open box, the sides of which, at 
its lower end, are concaved, to fit the periphery of the receptacle- 



BLACKING LEATHER. 



443 



roller e', which may be made to travel near the straight lower 
edge, 2, of the bottom of receptacle by means of the adjusting 
screws e^, the amount of space between the edge of the bottom 




Fig. 190. 




191. 




of the receptacle e and the roller e' determining the amount of 
blacking or dressing to be delivered to the brush c. The roller e' 
may be driven more or less rapidly to carry or de- 
liver more or less blacking or dressing to the 
brush c. This may be done by changing the size 
of the gear e^ on the journal of the roller e', the 
toothed speed-wheel /, which engages the gear e^ 
and drives the roller e', being mounted on a stud of 
an adjustable carrier,/', provided with a locking device, /2, to 
engage an arch,/^, and hold the carrier in proper position. 

It is preferable to slightly groove, flute, or pit the roller e\ to 
enable it to take up a greater quantity of blacking or dressing. 
The hide or skin as it leaves the supporting-surface a* is deliv- 
ered upon an endless belt or moving bed, (/, shown as composed 
of cords or tapes extended about rollers g' ^^, the one g' being 
driven positively from the toothed wheel h by the intermediate 
worm, A, which engages the pinion /?/ at the end of the shafts/'. 
The tanned h:de or skin to be dressed is introduced between 
the supporting-surface a^ and roller or brush c under a roller, ?, 
which, as clearly shown in Figs. 188 and 189, has its journals 
mounted on levers or arms l\ pivoted at V- and acted upon by 
springs Z^, to keep the roller depressed upon the hide or skin to 
properly hold it. The front ends of the levers or arms /' are 
joined to a holding-bar, w, which is of a shape to fit the space 
between the brush c, the support a^, and roller I. The under 



444: THE MANUFACTUEE OF LEATHEE, 

side of this holding-bar (see Fig. 189) is so shaped, curved, and 
located with relation to the surfaces of the roller I and the sup- 
porting-surface a* as not to bear upon the hide or skin until 
after the passage of the edges of the same beyond the nip of the 
roller ?, the holding-bar being devised to act upon and hold the 
end of the hide or skin, after passing beyond the nip of roller I 
(the latter then dropping), and prevent the hide or skin being 
drawn in too rapidly. In front of the apparatus there is placed 
a table, n. 

In some instances and for some classes of work the inventor 
modifies the machine so far described, as represented in Fig. 
191, and where there is shown the roller / as elevated consider- 
ably above the position shown for it in Figs. 188 and 189, and 
in such position there will be left sufficient space to permit the 
operator to retain hold of and control the position and move- 
ment of the hide or skin being acted upon by the brush or rol- 
ler c, and in such case also the holding-bar m is omitted. 

To prevent the blacking or dressing being thrown from the 
brush or roller c toward the front of the machine there is pro- 
vided the auxiliary spatter-guard o. The roller ?and the holder 
m, when used, also serve to prevent the blacking or liquid 
dressing from being thrown out at the front of the machine. 
The supporting-surface a^ and brush e are as long as the maxi- 
mum width of the hide or skin to be blacked or dressed ; but as 
the hides or skins being finished or dressed are always different, 
both as to width and outline at their edges, it results that the 
brush c always applies blacking or dressing to more or less of 
the surface a^. 

The blacking or dressing applied to the surface a* must all 
be removed and the surface be left clean so as not to apply 
blacking or dressing to the under side of the hide or skin as it 
comes in contact with it. To do this the inventor has provided 
a wiper or cleaner, p (shown clearly in Figs. 187 and 188), as a 
strip of flexible material held by a suitable adjustable bar, j9^, 
so that the edge of the wiper or cleaner may be pressed with 
more or less force against the surface a'*, the degree of its pres- 
sure being preferably regulated by adjusting-screws p^. The 
material wiped or scraped from the surface a* drops into the 



BLACKING LEATHER. 445 

trough q and passes therefrom iato a suitable pail or bucket to 
be rinsed, if desired. 

Bj driving the brush-roller c and the supporting-surface a* 
independently, the inventor is enabled to rotate either at any 
desired speed, and thus rub the blacking, coloring, or dressing 
matter more or less into the surface of the hide or skin. 

The bearings for the brush c and roller e' will preferably be 
made adjustable vertically to accommodate for the thickness of 
the leather and compensate for wear. 

Batchelder in 1883 patented an improvement on the machine 
just described, Avhich improvement is shown in Figs. 192 to 
195. In the machine described in Figs. 186 to 191, the brush- 
roller which applied the blacking or the liquid dressing to the 
leather on a rotating supporting surface or roll had its bristles 
set radial ; but with such a brush the distribution of the black- 
ing is not so uniform and thorough as is desirable, so, to cause 
the brush to apply the blacking to every minute part of the 
face of the leather being blacked or treated, Batchelder has 
inclined the bristles of the alternate rows of bristles of the brush 
in different directions, those of one row inclining toward one 
end of the cylinder and those of the next alternate row toward 
the opposite end of the cylinder, so that the ends of the bristles, 
besides travelling over the leather in the direction of rotation 
of the brush-roller, also, when in contact with the leather, spring 
or yield in opposite directions, the free ends of the bristles of 
alternate rows moving in opposite directions longitudinally as 
compared with the axis of the brush-roll, thus working the 
blacking backward and forward across the leather, as well as in 
the direction of its movement over the supporting-surface. In 
this way every particle of the upper side of the leather is effec- 
tually blacked and streaks are effectually prevented. 

Fig. 192 represents in section a sufficient portion of a leather 
blacking or dressing machine to illustrate the present improve- 
ment ; Fig. 193, an end view of the brush-roller on a larger 
scale ; and Figs. 194 and 195 two partial sections thereof in the 
dotted lines x and y. 

The supporting bed a*, color-roller e', deflector c?, spatter-roller 
Z/', and roller i are as in the machine shown in Figs. 186 to 191. 



446 



THE MANUFACTURE OF LEATHER. 



The roller c, which applies blacking to the leather B^ has its 
alternate longitudinal rows of bristles a h inclined in opposite 
directions, those of one row being as in Fig. 194, and those of 
the next row as in Fig. 195, so that as the bristles yield on coni- 



Fig. 192. 





Fig. 194. 


^i 


Fig. 195. 
6 


wim 


^^^^^%\ 


\yy^y//. 


y^>y 


1 - \ 


— -— -i 


W/Z/i^^/^A 




^/^ 


'^/A 


^tmmmmmm^m 





ing in contact with the leather B those of one row, as in Fig. 
194, will yield and move toward the left end of the brush-cylin- 
der, while those of the adjacent row (see Fig. 195), oppositely 
inclined, will move toward the right of the cylinder, the bristles 
of the two rows thus moving over the leather one after the 
other in opposite directions, in the direction of the length of the 
supporting roller a^, at the same time that all the bristles sweep 
over the leather as it is carried under it by the roller a*. In 
this way the blacking is brushed on the leather both longitudi- 
nally and transversely. The brush-cylinder has a metal jour- 
nal at each end, the journal preferably forming part of a metal 
shaft extended through the cylinder c of wood. The cylinder 
c is provided with a series of diagonal holes at opposite inclina- 
tions (see Figs. 194 and 195), into which the bristles a h are in- 
serted and held by glue and wooden plugs or galvanized nails, 
or in QXij usual manner. 



BLACKING LEATHER. 447 

Macliine for '■'• Sviutting'''' Leather. 

The macliine shown in Figs. 196 and 197 is the invention of 
Mr. Charles B. Bryant, of the firm of Messrs. Bryant & King, 
the well-known calf-skin tanners and curriers near Woburn, 
Massachusetts. 

In the manufacture of upper leather, after the skin has been 
tanned, it is removed from the tanning-liquor and shaved, and 
subsequently, while wet. is scoured or washed to remove from 
it the dirt. Scouring brings the leather into condition to be 
oiled or stuffed, after which, the leather having been dried, it is' 
whitened, and then grained and " boarded," as it is called, and 
thereafter blacked, and after blacking, the leather, to be fully 
finished, is " smutted." 

This invention has for its object the production of a machine 
for "smutting" leather, smutting being one of the processes or 
steps for the fine or better finishing of leather. That class of 
leather, calf-skin, etc., wherein the black face produced by or 
due to the application of lamp-black and an oleaginous material, 
is most commonly used in the manufacture of boots and shoes 
and other articles of leather without smutting, and the face of 
the leather shows a dull black the material of which easily 
cracks off"; but in some instances this black face is rubbed by a 
cloth and then by hand to rub the black into the leather and 
remove all surplus material therefrom, so that the black color 
will not rub off or smut when handling the leather. The process 
of smutting by hand — the only way it has been done up to the 
present time — is slow and expensive. In accordance with this 
invention, Bryant takes a hide or side of leather, blackened by 
machine or by hand, and subjects it to the action of rubbers or 
smutters and of brushes. The rubbers or smutters, by their 
friction against the leather, roll or rub up the black film or 
"skin," as it may be called, on the surface of the leather into 
small minute crumb-like particles, which are subsequently 
swept off or detached from the leather by the brushes. 

Fig. 196 represents in side elevation an apparatus embodying 
Bryant's invention, and Fig. 197 a view of the same from the 
left of Fig. 196. 



448 



THE MANUFACTURE OF LEATHER. 



A. represents a wheel or drum ori a shaft, B, having its bear- 
ings in standards G, the shaft being driven by a belt on the fast 
pullej D. 



Fiff. 196. 




The drum or cylinder A has attached to it a series of brushes, 
a a, the latter being shown as made adjustable with relation to 
the cylinder and the leather-supporting surface E by nuts /; c on 
bolts d, as will be understood from the drawings, so that the 




brushes may be made to act properly on the face of the leather, 
according to its thickness. Between the series of brushes, and 
preferably adjustably mounted on the said cylinder A, is a 



BLACKING LEATHER. 449 

series of rubbers or smutters, /, preferably composed of some 
sort of strong fabric. The inventor has used with good results 
pieces of Brussels carpet, and there might be employed for the 
rubbers or smutters either a fabric or a finer and softer brush 
than the brush a. 

This machine operates, to perform the work required of it, at 
a very rapid rate as compared with handwork, and does its 
work even better than can be done by hand, improves the qual- 
ity of the leather, and enables it to be sold for considerably more 
than the ordinary blacked leather which is not subsequently 
rubbed and finished as stated. 

List of all Patents for Apparatuses for Blacking Leather, issued hy 
the Government of the United States of America, from 1790 to 1883 
inclusive. 



No. 
107,625 


r 
Sept. 


>ate. 

20, 


1870. 


Inveutor. 
H. P. Reed and 
Thos. E. Wilson, 


Residence. 
Peabody, Mass. 


128,658 


July 


2, 


1872. 


H. P. Reed and 
Thos. E. Wilson, 


Peabody, Mass. 


227,204 ^ 

Reissue / 

9,794 ) 


May 
July 


4, 
12, 


1880. 
1881. 


F. B. Batchelder, 


East Boston, Mass. 


227,836 
251,401 


Feb. 
Dec. 


15, 

27, 


1881. 
1881. 


F. A. Dupuy, 
F. B. Batchelder, 


Ironton, Ohio. 
East Boston, Mass. 


271,971 


Feb. 


6, 


1883. 


F. B. Batchelder, 


East Boston, Mass. 



Section II. Blacking Compounds. 

The composition of the soap and oil blackings in common use 
by our American curriers has been described in the chapter 
treating the manufacture of upper leather, and the blackings 
Avhich are now to be described are some of the patented com- 
pounds which are sometimes employed. 

Flesh Blacking. 

The following compound was patented by Hayward in 1846. 
To make one gallon of this blacking, dissolve one pound of pure 
potash in two quarts of soft water, then add to it one pound of 
tallow, and boil them together one hour ; then dissolve one- 
quarter of a pound of potash in a quart of soft water, and stir 
29 



450 THE MANUFACTURE OF LEATHER, 

into it two-fifths of a pound of pure lampblack until it is well 
mixed, and add this decoction to the first one, and boil them 
together fifteen minutes. After which add one quart of "straits 
oil" and stir it well into the mixture and let it cool, and it is 
then ready for use. 

Compound for Finishing Upper Leolher. 

■ In 1877 Shaw obtained a reissue of his patent for a composi- 
tion for dressing leather, which is prepared as follows: First, 
one gallon of soft water, to which have been added six ounces of 
best extract of logwood, is heated nearly to the boiling point, 
but preferably not brought to boil, and is well stirred until the 
dye stuff' is dissolved, after which it is allowed to cool. Second, 
one gallon of soft water, to which have been added six ounces of 
borax, is likewise heated nearly to the boiling-point, until the 
borax is dissolved. To this are added one and one-half pounds 
of gum-shellac, the same being gradually introduced in small 
quantities, and stirred briskly until thoroughly dissolved. Third, 
three-eighths of an ounce of bichromate of potash are dissolved 
in half a pint of hot water, in a separate vessel. This consti- 
tutes a proper mordant for converting the logwood extract into 
a black dye or soluble coloring matter, possessing a blue-black 
shade or tint. 

Fourth, the first and second preparations are now added 
together by pouring the logwood solution into the solution of 
shellac, and stirring well until the two are intermixed. Then, 
while yet warm, the solution of bichromate of potash is added, 
and the whole briskly stirred for some time. This mixture is 
allowed to stand until entirely cool, and then, after skimming 
ofi' whatever may have risen to the top of it, the liquor is drawn 
off for use. 

To make a dressing which may be applied to leather in very 
thin coats, and at the same time produce a finer and brighter 
finish than could otherwise be obtained, mix with the liquor 
last described three or four ounces of concentrated water of 
ammonia or spirits of ammonia, and then put it up in cans 
tightly corked, ready to be applied to the leather. 

The dressing may be made thicker or thinner, as required. 



BLACKING LEATHER. 451 

Finislimg Split Leather. 

The following composition is the invention of Joel Putnam, 
and is for finishing the inner side of split leather and giving it 
an appearance closely resembling the grain side of " kip leather." 
In carrying out this invention, first make a composition of one 
pound of glue, one-half pint of boiled linseed-oil, and about one- 
half ounce of vermilion, or other suitable pigment. 

The glue should be dissolved in hot or boiling Avater, so as to 
make a solution of the consistency of such as is commonly used 
for cementing wood ; afterwards the oil and the pigment should 
be thoroughly incorporated or mixed with the solution of glue. 

The composition thus made is next to be applied to the sur- 
face of the piece of leather by means of a brush, two or anv 
other suitable number of coatings being so laid on, and each 
being allowed to become dry before application of the next one. 

After the application of each coating, it should be " glassed." 

Finally, the leather so coated should be boarded. 

List of all Patents for Blacking^ Compounds for Leather, issued by the 
Government of the United States of America, from 1790 to 1883 in- 
chisive. 



So. 


] 


Date. 




Inventor. 


Residence. 


2,431 


Jan. 


24, 


. 1842. 


N. A. Rowland and 
H. Miller, 


Rowan Co., N. C. 


2,660 


May 


30, 


, 1842. 


S. Adams, 


Cleveland, 0. 


2,844 


Nov. 


4, 


1842. 


T. P. Merriam, 


New Bedford, Mass. 


3,144 


June 


24, 


1843. 


P. Hairll and 
D. Curran, 


Roscoe, 0. 


3,401 


Jan. 


6, 


1844. 


W. J. Roome, 


New York, N. Y. 


4,498 


May 


9, 


1846. 


J. Hay ward, 


Cleveland, 0. 


23,065 


Feb. 


.22, 


1859. 


L. R. Rockwood, 


Worcester, Mass. 


34,530 ^ 


Feb. 


25, 


1862. ■i 






Reissue > 






\ 


M. Shaw, 


Abington, Mass. 


7,509) 


Feb. 


13, 


1877. } 






39,986 


Sept. 


15, 


1863. 


A. Bond, 


Philadelphia, Pa. 


47,082 


April 


■ 4, 


1865. 


R. Bartholow, 


Cincinnati, 0. 


47,957 


May 


30, 


1865. 


P. W. Keating, 


Norwich, Conn. 


50,383 


Oct. 


10, 


1865. 


D. L. Pickard, 


Rochester, N. Y. 


50,780 


Oct. 


31, 


1865. 


A. Tomlinson, 


Cincinnati, 0. 



^ See also list of patents for coloring compounds. 



452 



THE MAXUFACTUEE OF LEATHER. 



No. 


] 


Date, 




Inventor. 


Kesidence 


52,391 


Feb. 


6, 


1866. 


G. W. Corey, 


Port Jervis, N. Y. 


52,920 


Feb. 


27, 


1866. 


0. P. Whitman, 


Lynn, Mass. 


54,303 


May 


1, 


, 1866. 


J. A. Dean, 


Easton, Mass. 


54,616 


May 


8, 


, 1866. 


S. Sherwood, 


New York, N. Y. 


55,203 


May 


29, 


1866. 


T. James, 


Medford, Mass. 


56,526 


July 


24, 


1866. 


J. M. Butcher, 


North Lewisburg, 


57,567 


Aug. 


28, 


1866. 


N. F. Quimby, . 


Wilmington, Del. 


58,532 


Oct. 


2, 


1866. 


W. K. WykoflF, 


Ripon, Wis. 


59,851 


Nov. 


20, 


1866. 


J. McCrellish, 


Philadelphia, Pa. 


65,535 


June 


11, 


1867. 


A. Boudron, 


Philadelphia, Pa. 


66,982 


July 


23, 


1867. 


C. McCleary, 
(executrix,) 


Hollidaysburg, Pa. 


70,737 


Not. 


12, 


1867. 


W. B. Moor, 


Winchester, Mo. 


71,485 


Nov. 


26, 


1867. 


S. A. Hickel, 


Spencer, W. Va. 


73,730 


Jan. 


28, 


1868. 


H. Lake, 


San Francisco, Cal. 


76,897 


April 


.21, 


1868. 


J. Engelhardt, 


Carboudale, Pa. 


78,372 


May 


26, 


1868. 


J. Herold and 
M. Brown, 


Frederick, Md. 


83,817 


Nov. 


10, 


1868. 


S. S. Allen, 


Richmond, Md. 


93,002 


July 


27, 


1869. 


J. Putnam, 


Dan vers, Mass. 


94,897 


Sept. 


14, 


1869. 


J. Knapp, 


Syracuse, N. Y. 


97,857 


Dec. 


14, 


1869. 


L. Baumer, 


Columbus, 0. 


98,916 


Jan. 


18, 


1870. 


W. B. Bruthingham, 


La Fayette, Ind. 


103,402 


May 


24, 


1870. 


G. F. Whitney, 


Boston, Mass. 


111,133 


Jan. 


24, 


1871. 


E. Milner, 


Marquette, Mich. 


114,354 


May 


2, 


1871. 


H. A. Sawyer and 
R. G. Sawyer, 


Milwaukee, Wis. 


118,842 


Sept. 


12, 


1871. 


C. Brumly, 


Rochester, N. Y. 


119,239 


Sept. 


,26, 


1871. 


J. H. Patterson, 


Glen's Falls, N. Y. 


120,348 


Oct. 


24, 


1871. 


0. K. Tripp, 


Rochester, N. Y. 


124,760 


Mar. 


19, 


1872. 


H. A. Reams, 


Durham, N. C. 


128,873 


July 


9, 


1872. 


0. A. Goold, 


Portland, Me. 


131,245 


Sept. 


,10, 


1872. 


J. Breinig, 


Allentown, Pa. 


133,400 


Nov. 


26, 


1872. 


J. N. Baratta, 


Ayer, Mass. 


135,310 


July 


28, 


1873. 


F. G. Bell, 


New York, N. Y. 


141,829 


Aug. 


12, 


1873. 


A. D. Strong, 


Ashtabula, 0. 


144,801 


Nov. 


18, 


1873. 


J. L. Sneed, 


Frankfort, Ky. 


148,582 


Mar. 


17, 


1874. 


J. Townsend, 


Darby, Pa. 


155,206 


Sept. 


22, 


1874. 


C. E. Selss, 


Brooklyn, N. Y. 


155,860 


Oct. 


13, 


1874. 


J. Clausen, 


New York, N. Y. 


157,835 


Dec. 


15, 


1874. 


H. D. Jewett and 
J. D. Jewett, 


St. Omer, Ind. 


157,936 


Dec. 


22, 


1874. 


J. A. Sefton, 


Cleveland, 0. 


158,907 


Jan. 


19, 


1875. 


E. Clark, 


New York, N. Y. 


160,741 


Mar. 


16, 


1875. 


C. Alvord, 


Binghamton, N. Y. 


161,203 


Mar. 


23, 


1875. 


J. Carmody, 


New York, N. Y. 


162,394 


April 


20, 


1875. 


A. K. Lee, 


Galveston, Texas. 



MACHINES FOE GLAZING OR POLISHING, ETC. 



453 



No. 


Date 




Inveutor. 


Besidence. 


1(33,855 


June 1, 


1875. 


J. I. Eastman, 


Philadelphia, Pa. 


168,220 


Sept. 28, 


1875. 


J. H. Brown and 
J. G. Whiteside 


St. Louis, Mo. 


176,105 


April 11, 


1876. 


P. J. Weber, 


BuflFalo, N. Y. 


178,319 


June 6, 


1876. 


H. F. H. Miller, 


Boston, Mass. 


190,495 


May. 8, 


1877. 


C. L. Jones, 


Stoughton, Mass. 


203,138 . 


April 30, 


1878. 


J. H. Gordon, 


Brooks, Me. 


203,498 


May 7, 


1878. 


N. Quinland and 
J. H. Quinland, 


Glen's Falls, N. Y 
Jr., 


204,528 


June 4, 


1878. 


C. H. Broad, 


Rochester, N. Y. 


209,570 


Nov. 5, 


1878. 


J. H. Hyatt, 


Newark, N. .J. 


241,876 


May 24, 


1881. 


G. E. Millar, 


Austin, Nev. 


258,404 


May 23. 


1882. 


J. H. Garrett, 


Terre Haute, Ind. 


259,009 


June 6, 


1882. 


M. Hackett, 


New York, N. Y. 


259,188 


June 6, 


1882. 


E. N. McKimm, 


Lathrop, Mo. 


260,416 


July 4, 


1882. 


C. Richter, 


St. Paul, Minn. 


272,606 


Feb. 20, 


1883. 


J. A. Van-Keuren, 


Bridgeport, Conn. 


277,017 


May 8, 


1883. 


W. H. Durkee, 


Cincinnati, 0. 



CHAPTER XXYI. 

MACHINES FOE, GLASSING OE POLISHING, PEBBLING, FINISHING, 
EOLLING LEATHEE, ETC. 

The leather after being properly blacked is next glassed, and 
while this operation is sometimes performed by hand with a 
glass slicker, such as is shown in Fig. 198, still by far the 



Fig. 198. 




greater part of the leather curried in this country is glassed by 
machinery, and a large number of contrivances have been in- 
vented for this purpose as well as for pebbling, finishing, and 



45i THE MANUFACTURE OF LEATHER. 

similar operations. The scarcity of labor in all the Northern 
States from the commencement of the late war of the rebellion, 
and the enormous demand for leather which immediately arose, 
stimulated inventors in all lines of leather production, and 
machinery for this purpose which came into use from 1860 to 
1873 is still the kind that is now commonly employed in all 
sections of the country. 

Martin'' s Machine. 

Martin's machine, which is largely used by leather, Morocco, 
and lining finishers, was invented in 1860, and it is shown in 
perspective view in Fig. 199. 

Fiff. 199. 




The machine is simple in design and very compact, the action 
is easy and silent, and the adjustment can be accomplished with 
facility. It can be operated at a high rate of speed, and its 
general employment by our leading finishers is an evidence of 
the quantity and quality of the work which it will perform. 

In currying it will " set out," pebble, " stone out," " glass in 
black and paste," using either oil or soap blacking, entirely 
without hand labor. 

In Morocco and lining finishing the machine will glaze, roll, 
pebble, and glass out, and perform the work in a satisfactorj'- 
manner. 

Martin's invention, shown in detail in Figs. 200 to 203, con- 



MACHINES FOR GLAZING OR POLISHING, ETC. 



455 



sists in the employment, in combination with a yielding bed for 
sustaining the leather to be operated upon, of a reciprocatory 
carriage arranged about parallel with the bed, and a combina- 
tion of pivoted levers, whereby the tool-stock is carried along 
in contact with the bed and back over it. 

Fi?. 200. 




Figure 200 is a side elevation ; Fig. 20 L is a similar view, 
showing the parts in a different position; Fig. 202 is a detail 
section at the line x x of Fig. 200 ; and Fig. 203 is a detail 
sectional elevation of the work-table, which is omitted in Figs. 



Fig. 201. 




200 and 201 in order that the working parts of the machine 
may be more clearly delineated. 

C represents the base or floor, on which are secured the work- 
ing parts and the table and frame of the machine. 



456 



THE MANUFACTUEE OF LEATHER. 



The frame B^ the peculiar shape of which is clearlj seen, 
may be made of any suitable material of proper strength, and 
to the side of the projecting arm portion of this frame is secured 
the square working bar or way i), upon which travels the 



Fis. 202. 



Fi^. 203. 




reciprocatory carriage h. This carriage l is driven through an 
intermediate combination of pivoted levers by a pitman, c, con- 
nected at V to the main crank-pin on the driving-wheel A^ 
which latter may be rotated on its axis by any motive power. 
On the sill u is arranged the base-plate r of a metallic stand, j 
k k. At each end of this metallic stand is a screw-rod, on the 
lower end of which is a nut, s, and on which are arranged also 
two other nuts, o o', and a spiral spring, j:/. The lower one, o', 
of the two nuts o and o' is used to vary and control the action 
of the spring p on each bolt, while the upper nut, o, supports 
the adjusting-bar h. This bar has two inclined planes or oblique 
surfaces near its two ends, on which inclifleld surfaces rest the 
supporting blocks or lugs d d of the metallic bed c', on which 
the skin «/ to be operated on is placed. This bed c' may be 
covered on top with a stratum of leather, as seen at //, Figs. 
200 and 201. 

On one side of the adjusting-bar h is pivoted, at x, one end of 
a rod, ^, the other end of which has a nut in it, within which 
works the screw-rod v, which is provided with a knurled head, 
by means of which it is readily turned, for purposes to be ex- 
plained. 

/is the "hand" or tool-stock, in which is hung the tool e. 
To the carriage h is secured a plate, I to which, at y y, are pivot- 
ed one end of pitman c, where it is bent up, as at g, and one 
end of a link, m, the other end of the link m being pivoted in 



MACHINES FOE GLAZING OR POLISHING, ETC. 457 

tarn to one end of bar 7^, which latter is pivoted at its other 
end to the angle of pitman c y, and also to the hand / by means 
of the pivot or stud y^. 

The operation of the machine thus far described may be thus 
explained : The leather to be rolled, pebbled, or otherwise 
operated upon being properly placed on the yielding bed at a', 
and the bed adjusted by means of the nuts o o and sliding bar 
7i, the motive power is applied to the main wheel J., causing it 
to rotate in the direction indicated by the arrow, and through 
the pitman c impart a reciprocatory motion to the carriage h. 

At Fig. 200 the parts are shown as they are when the carriage 
h has just started on its downward stroke in the direction indi- 
cated by the arrow. It continues during this stroke to travel 
with the hand or tool-stock/ in such position that the roll e 
travels in contact with and pressing against the upper surface 
of the leather or other stock being worked upon. At about the 
completion of this stroke, and while the crank-pin v is passing 
a dead-centre, the relative position of the hand/ and carriage h 
is changed and the parts assume the position seen at Fig. 201, 
in which position the return or upward stroke of the carriage 
and pitman is made, the hand/, it will be understood, moving- 
back above and at same distance from the leather. As the 
crank-pin v passes over the next dead-centre the hand /is again 
thrown down on to the leather, as seen at Fig. 200, and another 
stroke is made, and so on the rubbing over the surface of the 
leather of the hand is continued. As the operation of the 
machine continues the yielding bed is manipulated by the ad- 
justment of the bar A, and supporting- nuts o o, and springs jj 7;, 
and is familiar to those skilled in the use of the machine. It 
will be seen that while the machine is running the adjustment 
of the yielding bed up and down may be effected by turning 
the screw-shaft v. It will be seen that the various operations 
of rolling, pebbling, glazing, finishing, etc., may be performed 
on various kinds of stock by placing different tools in the tool- 
stock as is shown in the drav/ings; audit will be understood 
that by means of the jam nuts 0' 0', in connection with the rods 
and springs p, the amount or degree of elasticity at each end of 
the yielding bed may be regulated and varied to suit the 



458 THE MANUFACTURE OF LEATHER. 

peculiar nature of the different portions of the stock being 
operated upon. 

Most of the features embraced in the yielding bed and its 
mechanism are so well known that we need not dwell upon that 
part of the description. 

The feature that is not generally understood is in the 
method of applying and working the hand or tool stock/, by 
attaching it to a system of levers involving a sort of parallel 
motion in conjunction with a reciprocatory carriage driven from 
a crank-motion. 

It is obvious that other peculiar combinations of pivoted 
levers and mechanical devices may be employed in connection 
with the carriage b, or its equivalent, to effect the same peculiar 
motion ascribed to the hand /, or to any tool which may be 
substituted for it. 

Friend's Machine. 

The glassing machine shown in Figs. 204 and 205 was in- 
vented in 1871 and further improved in 1875 by John P. Friend, 
and is adapted for work on all kinds of upper leather, sheep, 
goat, and Morocco. 

The bed of this machine is level, and arranged upon the 
principle of the platform scales, in order that it 'can be so ad- 
justed as to bring any point to bear either side wise or length- 
wise, and yet the turning of but one screw is required to 
increase or diminish the pressure uniformly. The pressure is 
equal at all points of the stroke, and may be increased suffi- 
ciently for pebbling without strain or injury to the machine. 

This machine is all within itself, and simply requires placing 
in position and securing, when it is ready for the belting, and 
when it is in motion there is but little "jar" or " shock". 

Fig. 204 shows a perspective view of Friend's machine. 

The pendulous arm A is pivoted to the frame B by the links 
or connecting-bars N and 0, which suspend and guide the vi- 
brating arm, and by which its vertical and vibratory movement 
is limited. The lower end of the arm A is connected with the 
foot C, and carries, with the foot (7, the tool-bar D^ which is 
connected at the upper end with the pendulous arm by the link 



MACHINES FOE GLAZING OE POLISHING, ETC. 



459 



E. A connecting-rod, F^ is attached to the foot C and to a 
crank or crank-wheel, by which a vibratory movement is given 
to the machine. 

Fig. 204. 




Fiff. 205. 







Fig. 205 shows a vertical section through the table of Friend's 
machine. 

A represents the frame of the machine. B the bed-plate, 
upon which the leather to be finished is laid. The top of the 
frame A incloses and holds the bed- 
plate in position. G is the first lever 
below the bed-plate ; it is jointed to 
it by the stud D. Below the lever 
Cis another lever, E^ and the fulcrum 
F \'& placed between the levers (7 and 
E. The bed-plate B and lever E 
are connected at the front of the 
machine by the bolt or connecting- 
rod G^, and the distance between the 
lever E and bed-plate B is adjusted by the nut and screw H. 
The front end of the lever ^ is supported by the spring /, which 
works on the standard J", and the tension of the spring is con- 



^^^^m 



460 



THE MANUFACTURE OF LEATHEK. 



trolled by the nut K. It will be seen that, by this arrangement 
of levers, the adjustment of the bed is had entirely from the 
front of the machine. In all the machines used for glassing 
leather it had been the practice prior to this invention to employ 
one or more springs under each end of the bed, so that the tool 
when in the middle of the bed was resisted by the combined 
force of the two springs, while, when it was at either end of 
the stroke, it had the force of only one. This inequality of pres- 
sure is avoided by the use of the devices shown in Fig. 205, and 
the pressure is equalized through the w4iole of the stroke ; and 
the vertical movement of the bed is parallel, and it does not 
rock at each reciprocation of the tool, as it does in the use of two 
or more springs. 

Hildretli's Machine. 

The machine for glassing, and which is also largely used for 
pebbling leather, invented in 1868 by Joseph W. Hildreth, is 
shown in Figs. 206 to 208. 



Fig. 206. 



Fig. 207. 




Fig. 206 shows a vertical, central, and longitudinal section of 
a common form of a " leather glassing" or polishing machine, 
and Fig. 207 a vertical and transverse section of such a machine 
with Hildreth's improvement applied thereto. 




MACHINES FOR GLAZING OR POLISHING, ETC. 461 

Fig. 208 is an enlarged side elevation of a portion of the 
machine, showing the elastic bearing to be hereafter described. 

A denotes a metallic bed, concave upon its npper surface, 
resting upon and supported at each end by an elastic cushion or 
spring, the bed thus supported being upheld 
by a suitable framework applied to the floor of ^"' 

an apartment or building in which the machine 
is located. 

A large number of the machines for glassing 
leather, prior to Hildreth's invention, were con- 
structed so that as the polishing tool approached 
the centre of the bed A, the pressure upon the 
leather increased, and the leather became distended and bagary, 
and reduced in thickness in its central portion. 

The object which Hildreth had in view in the invention of 
his machine was to obviate this defect by equalizing the distri- 
bution of the pressure upon the finishing-bed and leather. 

Hildreth makes the point of suspension of the vibrating arm 
c an elastic one, in order to accomplish this. 

The mode of applying the elastic bearing is as follows : The 
lever c is upheld by a horizontal cross-bar extending into guides 
or slots, m, w?, made through the side bars a' a' of the arm c/, 
the lever c swinging between the two. 

A spring, w, composed of India-rubber or other suitable 
material, is placed on top of each end of the cross-bar ?, and 
within the slots m, m, as shown in Fig. 207. 

A set-screw, o, is screwed through a cap-plate, p, applied to 
each bar a', and over and closing the slots m, m, such set-screws 
pressing down upon a metallic plate placed over the top of each 
spring n, 7i, and serving to regulate pressure of such springs 
upon the cross-bar l. 

If considered necessary or desirable, metallic blocks, recessed 
for reception of the end of the springs n, n^ may be interposed 
between the cross-bar /, and such springs to retain them in place, 
the blocks being formed with splicers or projections upon each, 
to slide in grooves made in the inner faces of the slots m, m. 



462 



THE MANUFACTURE OF LEATHER. 



Baker^s Improved No. 4 Olazing Machine. 

Baker's former machines for glazing leather have been in 
use bj a number of the leading houses in the Morocco trade, 
both in this country and Europe, and have given universal 
satisfaction. 

But the great advancement towards perfection in the Morocco 
business, requires an equal perfection in machinery for develop- 
ing the art. Mr. Baker, having this in view, has added to 
his already successful machine some important improvements, 
which will at once command the attention of the progressive 
manufacturer. This new glazing machine, which is shown in 
Fig. 209, has been reduced in size to economize in space, yet 

Fig. 209. 




without lessening its capacity for doing the widest range of 
work. Another important point is, that the balance cranks 
have been substituted by a balance wheel and crank combined, 
thereby giving the advantage of the balance wheel, both of 
which, when placed inside the main frame, give it the required 
stability of the balance cranks with the advantage of the balance 
wheel having the power stored in it to overcome the dead cen- 



MACHINES FOE GLAZING OE POLISHING, ETC. 463 

tres and return the beam witli ease over the glazed surface of 
the leather. Another improvement claimed, is the new style 
clamp or holder, for holding the glass or agate; this clamp can 
be removed to put on any of the different rolling and pebbling 
attachments as readily as before. The horse or buck has been 
improved by the application of an arrangement for tilting the 
bed, in case the bed-strap should not be entirely parallel with 
the glass, which is performed by means of thumb-screws on 
the side, thereby saving time, and overcoming that imperfection 
in the stroke known to the trade as " cornering." 

Baker's Pony Glazing Machine. 

Baker's Pony Glazing Machine is shown in Fig. 210. 

For a long time Morocco manufacturers have desired a 
machine that would perform all the work that the old-fashioned 
" buck" would do, and without its many disadvantages, and at 

Fio;. 210. 




the same time at a cost that would not exceed that machine. 
To accomplish this end, Mr. G. W. Baker invented the pony 
glazing machine, as illustrated above. 

It requires but a small space, and is so constructed as to do 



464 THE MANUFACTURE OF LEATHER. 

anjr kind of glazing in a superior manner. The framework is 
made of wood ; all tlie working parts are of iron, such as the 
crank shaft, pulley, and bearings, rock-arms, wrist-clamp, for 
holding the glass or agate, and are thoroughly substantial. 

The horse or " buck" is entirely of iron, provided with springs 
and screws that move independently of each other, and in such 
a manner that the pressure on the skin can be regulated to a 
nicety. It uses the improved glazing strap, which stands highly 
with the trade for durability and the performance of good wopk. 

Overhead Glazing Machines. 

There is a class of the Morocco trade that uses an overhead 
glazing machine made of wood in several parts. One part, 
including the beam, is fastened to the joists above, with the iron 
horse immediately below it resting on the floor, and a short dis- 
tance from the horse two upright posts are bolted to the joists 
with space between them for the iron balance-wheel. A wood 
connecting-rod connects the wheel with the beam, and all the 
working parts have metal bushings. It can be used very well 
in a good strong building, but where there are more than two, 
it makes too much strain on the floors, as they receive all the 
pressure, the force of the roller on the strap having a tendency 
to push the beam upwards, as it is fastened to the joists, and to 
push the horse downwards, thus causing the floors to be con- 
stantly vibrating. 

There are quite a number of these machines in use, but parties 
will have more satisfaction from a portable machine; it requir- 
ing time and expense to change them, and when once removed 
being useless. 

Those who have suitable buildings and wish this machine, 
however, will find it to do good work. 

Knox's Machine. 

The Morocco finishing and pebbling machine made by David 
Knox, is shown in Fig. 211. A medal and diploma were 
awarded to this machine at the Philadelphia Exposition of 1876 ; 
but since that time it has been improved and simplified. 

The machine is easily adjusted, and requires but little power 



MACHINES FOR GLAZING- OR POLISHING, ETC. 



465 



to operate it, and Morocco and lining finishers hold it in high 
esteem. In a tour through the Morocco tanneries of the city of 

Fi-. 211. 




Philadelphia, Pa., during the autumn of 1883, the author counted 
more than one hundred of these machines in operation in that 
city, which is asufficientguaranteeof the excellence of their work. 

List of all Patents for Machines for Stoning., Polishing., Finishing., 
Glassing, Glazing, Flinting, Creasing, and Dicing Leather,^ issued 
by the Government of the United States of America, from 1790 to 
1883 inclusive. 



No. 


Date 




lEventor. 


Residence. 


3,957 


Mar. 15, 


1845. 


R. Bracket, 


Boston, Mass. 


4,534 


Aug. 29, 


1871. 


A. W. Pratt, 


Salem, Mass. 


7,433 


June 18, 


1850. 


E. Brookout and 
H. Cochen, Jr., 


Williamsburgh, N. Y 


9,292 


Sept. 28, 


1852. 


J. M. Poole, 


Wilmington, Del. 


10,379 


Jan. 3, 


1854. 


P. T. Tapley, 


Lynn, Mass. 


12,806 


May 1, 


1855. 


N. Ames, 


Sangus, Mass. 



1 For other machines for glassing leather see list of patents for scouring 
machines on page 407, some of which are also used for glassing leather. 
30 



466 



THE MANUFACTURE OF LEATHER. 



No. 


Date. 




Inventor. 


Eesidence. 


13,605 ^ 


Sept. 25, 


1855. 


C. Weston, 


1 


Reissue } 






T. F. Weston, 


J- Salem, Mass. 


839 ^ 


Oct. 18, 


1859. 


J. W. Weston, 


I 


14,606 


April 8, 


1856. 


W. P. Gamble, 


Philadelphia, Pa. 


14,821 


May 6, 


1856. 


E. L. Norton, 


Charlestown, Mass. 


16,114 


Nov. 25, 


1856. 


W. Crane, 


Brooklyn, N. Y. 


20,861 


July 13, 


1858. 


J. R. Bumgarner, 
and L. W. White, 


Davenport, la. 


24,139 


May 24, 


1859. 


T. Newhall, 


Lynn, Mass. 


- 24,344 


June 7, 


1859. 


T. F. Weston, 


Salem, Mass. 


26,792 


Jan. 10, 


1860. 


R. L. Smith and 
C. Smith, 


Stockport, N. Y. 


26,932 


Jan. 24, 


1860. 


R. A. Stratton, 


Philadelphia, Pa. 


27,028 


Feb. 7, 


1860. 


G. S. Adler, 


Philadelphia, Pa. 


27,300 


Feb. 28, 


I860. 


W. P. Martin, 


Salem, Mass. 


27,885 


April 17, 


1860. 


R. P. Boyce, 


Erata, Miss. 


28,108 


May 1, 


1860. 


W. P. Martin, 


Salem, Mass. 


28,562 


June 5, 


1860. 


S. P. Cobb, 


South Danvers, Mass. 


31,879 


April 2, 


1861. 


W. Ellard, 


Woburn, Mass. 


40,735 


Dec. 1, 


1863. 


S. P. Cobb, 


South Danvers, Mass. 


41,363 


.Jan. 25, 


1864. 


J. G. Bushfield, 


Feltonville, Mass. 


48,186 


June 13, 


1865. 


R. Lee, 


Newark, N. J. 


52,728 


Feb. 20, 


1866. 


W. P. Martin, 


Salem, Mass. 


66,125 


June 25, 


1867. 


F. J. Burcliam, 


Racine, Wis. 


76,914 


April 21, 


1868. 


J. W. Hildreth, 


Bostoi;if, Mass. 


79,070 


June 23, 


1868. 


J. F. Harris, 


Swampscott, Mass. 


80,829 


Aug. 11, 


1868. 


P. Lenox, 


Lynn, Mass. 


85,030 


Dec. 15, 


1868. 


C. Schmitz, 


Philadelphia, Pa. 


91,219 


Jan. 15, 


1869. 


P. Farrell, 


Albany, N. Y. 


109,205 


Nov. 15, 


1870. 


H. C. Havemyer 
and D. P. Burden, 


New York, N. Y. 


114,809 


May 16, 


1871. 


D. Harrington, 


Boston, Mass. 


115,312 


May 30, 


1871. 


B. R. Hamilton and 
S. Swan, 


Deerfield, Mass. 
Conway, Mass. 


117,877 


Aug. 8, 


1871. 


J. P. Friend, 


Peabody, Mass. 


118,146 


Aug. 15, 


1871. 


G. H. Parker, 


Detroit, Mich. 


121,727 


Dec. 12, 


1871. 


N. D. Morey, 


Saratoga Springs, N. Y. 


122,136 


Dec. 26, 


1871. 


A. Shedlock, 


Brooklyn, N. Y. 


122,395 


Jan. 2, 


1872. 


C. A. McDonald, 


Woburn, Mass. 


123,681 


Feb. 13, 


, 1872. 


G. Crossley, 


Philadelphia, Pa. 


132,901 


Nov. 12^ 


, 1872. 


H. Cunningham, 


Albany, N. Y. 


139,442 


May 27, 


, 1873. 


W. A. Watson, 


Beverly, Mass. 


150,849 


May 12, 


, 1874. 


W. Ellard, 


Woburn, Mass. 


152,711 


June 30, 


1874. 


W. Walter, 


Yonkers, N. Y. 


158,761 


Jan. 12, 


, 1875. 


J. T. Tullis, 


Glasgow, North Britain, 


163,063 


May 11, 


, 1875. 


J. P. Friend, 


Peabody, Mass. 


170,983 


Dec. 14, 


, 1875. 


B. M. J. Blank, 


Jersey City, N. J. 



MACHINES FOR GLAZIN"a OR POLISHING, ETC. 



467 



No. 


Date. 




Inventor. 


Residence. 


173,178 


Feb. 8, 


1876. 


W. A. Perkins, 


Salem, Mass. 


207,930 


Sept. 10, 


1878. 


A. J. Alexander, 


Gallipolis, 0. 


208,918 


Oct. 15, 


1878. 


C. Molinier, 


Buzet, France. 


229,895 


July 13, 


1880. 


J. Liedtkie, 


Brooklyn, N. Y. 



List of all Patents for Machines used for Pebbling Leather^ issued hy 
the Government of the United States of America^ from 1790 to 1883 
inclusive. 



No. 


Date. 




Inventor. 


Residence. 


14,821 


May 


6, 


1856. 


E. L. Norton, 




27,300 

28,108 


Feb. 
May 


28, 
1, 


1860. 
1860. 


I W. P. Martin, 


Salem, Mass. 


42,136 


Mar. 


29, 


1864. 


C. T. Woodman, 


Boston, Mass. 


48,876 


July 


18, 


1863. 


G. W. Pratt, 


Salem, Mass. 


60,115 


Dec. 


4, 


1866. 


J. C. Armes, 


Northamj)ton, Mass. 


76,914 


April 21, 


1868. 


J. W. Hildreth, 


Boston, Mass. 


117,877 


Aug. 


8, 


1871. 


J. P. Friend, 


Peabody, Mass. 


119,743 


Oct. 


10, 


1871. 


0. Coogan, 


Pittsfield, Mass. 


132,901 


Nov. 


12, 


1872. 


H. Cunningham, 


Albany, N. Y. 


135,350 


Jan. 


28, 


1873. 


N. 0. Lounsberry, 


Wilmington, Del. 


140,633 


July 


8, 


1873. 


N. 0. Lounsberry, 


Wilmington, Del. 


155,931 


Oct. 


13, 


1874. 


M. Dolan, 


Boston, Mass. 


157,632 


Dec. 


8, 


1874. 


P. O'Brien, 


Boston, Mass. 


159,092 


Jan. 


26, 


1875. 


A. M. L. Groflf and 
J. A. Marvel, 


Wilmington, Del. 


161,046 


Mar. 


23, 


1875. 


N. 0. Lounsberry, 


Wilmington, Del. 


161,269 


Mar. 


23, 


1875. 


A. W. Perrin, 


New York, N. Y. 


163,063 


May 


11, 


1875. 


J. P. Friend, 


Peabody, Mass. 


168,497 


Oct. 


5, 


1875. 


H. Howson, 


Philadelphia, Pa. 


176,535 


April 25, 


1876. 


L. R. Jenkins, 


Philadelphia, Pa. 


205,974 


July 


16, 


, 1878. 


E. B. Parkhurst, 


Woburn, Mass. 


246,278 


Aug. 


30, 


, 1881. 


E. C. Allison, 


Melrose, Mass. 



List of all Patents for Machines for Rolling^ Leather, issued hy the 
Government of the United States of America, from 1790 to 1883 in- 
clusive. 

Residence. 



No. 



37,991 
40,069 
50,079 
71,929 



Date. Inventor. 

Oct. 19, 1812. W. Edwards, 

April 28, 1836. McLaughlin and Hill, Sunderland, Vt. 

Mar. 24, 1863. J. Whitney, Winchester, Mass. 

Sept. 22, 1863. J. Whitney, Winchester, Mass. 

Sept. 19, 1865. D. H. Priest, Boston, Mass. 

Dec. 10, 1867. J. H. Walker, Worcester, Mass. 



^ This list also includes machines for rolling sole leather. 



468 THE MANUFACTURE OF LEATHER. 



Ko. 


Date, 




Inventor. 


■Residence. 


93,465 


Aug. 10, 


, 1869. 


C. W. Monson, 


Upton, la. 


98,889 


Jan, 18, 


1870. 


J. F. Safford, 


Winchester, Mass 


101,197 


Mar. 22, 


1870. 


H. J. Weston, 


Buffalo, N. Y. 


101,234 


Mar. 29, 


1870. 


G. Curtis, 


Emporium, Vt. 


115,443 


May 30, 


1871. 


G. Curtis, 


Emporium, Vt. 


124,709 


Mar. 19, 


1872. 


J. Whitney, 


Winchester, Mass, 


149,906 


April 21, 


1871. 


J. Whitney and 
A. E. Whitney, 


Winchester, Mass, 


151,989 


June 16, 


1874. 


S. R. Krom, 
/ N. Lindsey, 


New York, N. Y. 
) 


171,574 


Dec. 28, 


1875. 


■| J. McCuUough, and ' 
(w. Clement, I 


> Lena, HI. 


171,867 


Jan, 4, 


1876. 


Win. H. Rosensteel, 


Johnstown, Pa. 


176,763 


May 2, 


1876. 


J. C. Wells, 


Warren, Pa. 


194,352 


Aug. 21, 


1877. 


H. Hudson, 


Saltillo, Pa. 


194,906 


Sept. 4, 


1877. 


A. Hanver, 


Union, N. Y. 



CHAPTER XXYII. 

Machines for Measuring Leather. 

The heavy leathers are sold by weight ; but light leathers, 
such as upper, Morocco, sheep-skin, and enamel leather, are 
sold by area. The yardstick, and the common measuring 
frame, having wires or cords running the length and across it, 
thus dividing the frame into square feet, do not require special 
description ; but since 1877 there have been invented in the 
United States seven different leather-measuring machines, and 
taking Lynn, Mass., as the centre, all of them have been in- 
vented by persons living within a radius of about twenty-five 
miles of that place. 

The leather- measuring machine invented by David T. Winter, 
of Peabody, is a convenient contrivance for measuring. The fault 
found with it by finishers of leather was that after purchasing 
the machine they were compelled to pay a royalty for its use to 
other parties who had gained a suit against Winter for an in- 
fringement of their patent rights. But Mr. Winter has lately 



MACHINES FOR MEASURING LEATHER. 



469 



secured the control of a leather-measuring machine which is 
thought to be free from the objections to the one just men- 
tioned. 

Williams, Moore, and Hulhuris Leather-Measuring Machine. 

The leather-measuring machine shown in Figs. 212 to 216 
was invented bj Williams, Moore, and Hulburt, in 1879. 

The operation of the machine is as follows : The table D be- 
ing raised, as shown in Fig. 212, the skin or article to be meas- 
ured is spread upon the table B, and the table D, carrying the 
pins r r, is brought down upon it, assuming a horizontal position 
before reaching it, and the pins are deposited in a perpendicular 
position upon the weighing-platform C, except such as are inter- 
cepted by the skin. (See x, Fig. 213.) 

Fig. 212. 




The dial/ being so marked that when all the pins rest upon 
the weighing platform the pointer will indicate 0, and the pins 
upon each square foot of surface that are removed from the 
weighing platform allowing the pointer to recede a space 



470 



THE MANUFACTURE OF LEATHER. 



marked one foot, the area in square feet is indicated correctly, 
except as far as the brake S may prevent it. A slight pressure 
then applied to the end of the rod v, forcing it back, removes 
the pressure of the brake S and allows the pointer on the dial/ 
to indicate exactly the correct measurement. 



Fig. 213, 




Fig. 212 is a perspective view; Fig. 213, a vertical cross- 
section at line w, Fig. 212 ; Fig. 214, a diagram showing the 
position of the table carrying the pins and its supporting-levers 
at different elevations ; Fig. 215, an interior end elevation ; and 
Fig. 216, a modified form of pin. 





1 ,*>. i^.- 


Fig. 

""'ft--'""" 


214. 

1 ' .■•<» ; 


7/^ 


•••■■V} 




l^ 




i:,//;^ D ^ 


7fl" 






'•^J ^^ 


i 


' ^l 


m 






%y ) 




■^"'m Jt 




^^A 


f \ 



The following is a description of the manner in which this 
machine may be constructed : The table D is four and one-half 
feet Avide, the shaft E may be nineteen and one-half inches 



MACHINES FOR MEASURING LEATHER. 



471 



below the same, and fifteen inches from tlie rear side of tlie 
frame A. The arms i and k and the bars h and g sliould be of 
tlie following lengths, measuring from the centres of their 



Fig. 215, 




pivotal points in each case : arm i, nine inches ; arm k, twelve 
inches; bar A, twenty-two and one-half inches; bar ^, thirty- 
eight inches. The upper end of bar h should be pivoted to the 
table D thirteen and one-half inches from its rear side, and bar 
g twenty-five inches from bar h, and fifteen and one-half inches 
from the front side of table. The arms i and k are at such an 
angle to each other that the distance from the extreme pivotal 
point of one to the same point in the other is thirteen and one- 
half inches. These dimensions may be varied to suit the condi- 
tions required. 

Upon the shaft ^ is a hub with a radial arm carrying a 
weight, TF", so that as the shaft is turned in either direction the 
weight is moved in the arc of a circle of which the shaft E is 
the centre. If the arm carrying the weight TF be adjusted (by 
a set-screw in its hub) in a perpendicular position over the shaft 
JE when the table D is at its lowest point, it will be readily seen 
that in this position the weight W exerts no upward pressure 



472 THE MANUFACTURE OF LEATHER. 

on the table D. If, now, the table be raised from its lowest to 
its higbest point, the weight if will, by the turning of the shaft 
E^ be moved from its position over it to one at its rear, and 
thus exert a gradually increasing pressure against the table D. 
It is preferable to set the arm carrying the weight at a slight 
angle backward from a perpendicular position over the shaft E 
when the table D is at its lowest point ; but any adjustment may 
be'made that will suit the convenience of the operator, it being 
understood that as the table D^ carrying the pins or weights, 
approaches and the pins are supported by the weighing plat- 
form, it is necessary, for ease of operation, that the table D 
should be at least partially relieved from the upward pressure 
of the weight W. 

The pins, which are represented in Fig. 212 as suspended in the 
table D^ and are shown in section in Fig. 213, are formed with 
a slender shank or body and a base of sufficient size and weight 
to enable them to stand upright without side support when de- 
posited in a perpendicular position upon a level surfice. The 
heads by which they are suspended are the frustums of cones 
having their larger diameters uppermost, and are of sufficient 
length to hold the pins firmly in a perpendicular position when 
placed in holes in which they fit closely. 

The holes in the table B are so arranged that when the table 
D is brought down upon it they coincide with those in D^ and 
are of such a size that the bases of the pins will readily pass 
through them. These pins are of such a length that when their 
bases rest upon the weighing-platform C, and the table ]) has 
been brought close down upon i?, their head^ will project for at 
least their entire length above the table D, and thus be free 
from contact therewith. This construction allows the pins to 
stand on the weighing-platform entirely free from support by 
the table D, and admits of an accurate weighing of the pins, 
which is impossible in machines as heretofore made. 

Fig. 216 represents another form of pin, which accomplishes 
the same purpose in a slightly different way. The head of this 
pin is cylindrical, and is prevented from slipping through the 
table in which it is supported by a slight contraction of the hole 
just at its lower surface, as shown at A", and it has no enlarged 



MACHINES FOR MEASURING- LEATHER. 173 

base, but is slightly rounded or pointed, so it may readily enter 
a hole or socket in the weighing-platform, by which it is sap- 
ported in an upright position. 

In practice the tapered heads, as shown in the main drawings, 
are often preferable ; but the pointed pin may be used with ad- 
vantage in certain cases. 

It has been found that the oscillation of the pointer of the 
dial/, connected with the weighing mechanism, is an obstacle 
to rapid work. This is overcome by means of a brake or lever, 
aS', pivoted to the frame A at t, and held lightly against the end 
of lever c by a spring, m, one end of which is attached to the 
front part of the frame A and the other to the brake s or the 
rod V, which is attached to it at s, and which extends across to 
the front of the machine, as shown. The spring may, for con- 
venience, encircle the rod, as shown. 

By pressing the projecting end of the rod v backward the 
brake may be removed from contact with the lever c. This 
may be arranged so as to operate automatically by the descent 
of the table D ; but it is preferable to operate it with the knee 
of the operator. 

Saioyer''s Leather- Measuring Machine. 

The Sawyer self-adjusting leather-measuring machine is 
shown in Figs. 217 to 224, and it is constructed on a different 
principle from other machines for measuring the areas of sur- 
faces, and it can be operated either by hand or power. 

A minimum of power will run this machine, and it can be 
operated at a fast or slow rate of speed ; 40 revolutions per 
minute is a good average, which gives five sides in that time. 
Wax, grain, enamel, goat and sheep-skins are perfectly meas- 
ured by this machine, which is made in different sizes to suit 
the various leathers. The machine is made of metal, and any 
of the series of wheels may be removed or replaced without inter- 
fering with the others. 

In machines of this class as first constructed the cords from 
all the winding devices were connected to one and the same 
cord, which actuated the index-finger of the scale. This ar- 
rangement was found objectionable on account of the friction 



474 



THE MANUFACTUEE OF LEATHER. 



caused by the great number of pulleys required and the diffi- 
culty with which the long cord rendered through them. 

One object of this invention is to obviate these objectionable 
features; and Sawyer's invention consists in an arrangement of 
levers by which the travel of each measuring-wheel is caused to 
properly aft'ect the index of the registering device. 

The article to be measured is fed into the machine between 
the wheels and roller, and the leather is smoothed out as it 
passes between them and so records every inch in the surface. 

Fig. 217 illustrates a perspective view of the front of the 
Sawyer Machine. Fig. 218 a partial rear elevation of the 

Fiff. 217. 




.1 !'' '- 



1 



,.-■■' < I 1 «■ 







machine with the latest improvements embodied. Fig. 219 is 
a view, on a larger scale, of one set of five cords and their por- 



MACHINES FOR MEASURING LEATHER. 



475 



tions of the main cord, showing the connection with the system 
of levers. Fig. 220 is a partial cross-section, showing a novel 



Fiff. 218. 




way of supporting the toothed segments, so as to allow the 
removal of any one of the wheels without disturbing the others. 

Fig. 219. 




Figs. 221 and 222 are details of the toothed-segments support. 
Figs. 223 and 224 are modifications of the system of levers. 
The width of the machine depends upon the number of wheels, 



476 



THE MANUFACTURE OF LEATHER. 



and varies for different varieties of leather, as has been stated. 
In Fig. 218 is illustrated one of the largest size for measuring 
enamel leather, made from whole hides, and is provided with 



Fig. 220. 




forty wheels. In all, however, each wheel is a separate 

measuring-machine, so that each machine will measure widths 

^ varying from that of one wheel up to the total number of 

wheels. All the wheels A rest on a roller, £, which is revolved 



MACHINES FOR MEASURING LEATHER. 



477 



by any of the well-known means. Bach wheel has a hub pro- 
jecting slightly beyond its rim and side. Each projecting part 
of the hubs is toothed, and is placed immediately below a 
toothed-segment (marked C in Fig. 220). To each of the hubs 



Fig. 221 



Fiff. 222. 



pa 




H 



of these segments is attached a cord, D. When an article — 
such as a side of leather — is inserted between the wheels A and 
the roller B^ a greater or less number of the wheels, according 
to the width of the article, will be raised, and their toothed hubs 




be caused to engage with the teeth of the segments C. As the 
article is drawn in by the revolution of the roller B^ the wheels 
in contact therewith will rotate and cause the segments with 
which their hubs mesh to rotate and wind up the cord attached 
to their hubs, and the total length of cord so wound up will 
indicate the total area of the article that passed under the wheels. 
To aggregate the measurements of the cords by means of a series 
of levers, the cords may be divided into sets, as indicated by the 
letters d, d! ^ d^^ #, d'^, cZ^, cZ^, and d^ in Fig. 218. Bach cord is 
secured at each end, c^^, to a small lever, cZ^, but renders freely 
through rings or pulleys. Two of these small levers d^ are 



478 THE MANUFACTUEE OF LEATHER. 

pivoted at their centre to the opposite ends of a lever, d^°, which 
may be pivoted at its centre direct to a weighted arm, F, 
pivoted to the frame at/, and carrying a racked segment,/', 
which, meshing with the pinion g, causes it to revolve when the 
arm i^is moved. The index-finger G is fast to the shaft of the 
pinion f/, and consequently moves with it. This arrangement 
would constitute a complete machine of ten wheels. For a com- 
plete machine of twenty wheels, two levers, c?^*', each having 
two small levers, d^, with their two sets of five cords, would-be 
pivoted to the arms of a lever, d^^, which would be pivoted at 
its centre to the weighted arm F. For the machine of forty 
wheels (illustrated in Fig 218), two of the twenty-wheel con- 
nections above described are pivoted to the ends of a lever, d^'^, 
which is pivoted at its centre to the weighted arm F. By thus 
shortening the cords the inventor is enabled to substitute for 
them small chains, which not only render freely and work per- 
fectly, but are also much preferable on account of not being 
affected by moisture and of their greater durability. The 
toothed segments, cords, and levers being arranged as has been 
described, the same amount of displacement of any one or other 
member of the segments will cause the index-finger to move the 
same distance over the graduated scale. The movement of the 
index-finger is always exactly proportional to the number of 
segments displaced and the aggregate amount of their displace- 
ments — that is to say, in measuring a surface of one hundred 
and forty-four square inches area, it would make no difference 
whether it were a strip, one and a half inches wide and ninety-six 
inches long, and rotated only one wheel during 'its passage, or 
whether it were a piece nine inches wide and sixteen inches 
long and rotated six wheels during its passage, or whether it 
were of varying widths in its length and rotated 'a different 
number of wheels according to its varying widths. The index- 
finger would in each case indicate the correct area. 

It will be obvious that the arrangement of levers may be 
varied, the requirement being that the arrangement shall be such 
as to correctly aggregate the motion of every measuring-wheel. 
Thus in Figs. 228 and 224 the wheels are shown in pairs, one 
cord from each pair extending round a pulley, and two of these 



MACHINES FOR MEASURING LEATHER. 479 

pulleys on each small lever d^. These small levers are connected 
in pairs by the levers c?^^, and each pair of levers d}^ is connected 
by a lever, c?'*, each lever (/^, in this case, being connected with four 
wheels — two at each end — each lever c?^^ with eight wheels, and 
each lever d^* with sixteen wheels, as shown in Fig. 223. Now, 
were there but thirty-two wheels in the machine, two levers d^^ 
would be connected — one at each end — with lever d^"^] but if 
forty wheels be nsed, then each lever d^* should be connected to 
a lever, c?'^, and these two levers d^^ should be each connected 
with a lever d^^ connected with eight wheels to make up the 
forty, and as the levers fP** have sixteen wheels at their outer 
ends and but eight wheels at their inner ends, or four for each 
lever d^^^ the levers d^^ should each have an arm four times as 
long as the other arm. 

Figs. 220, 221, and 222 illustrate the new way of supporting 
the toothed segments C, so as to allow any one of them to be 
removed when required to take out or replace any one of the 
wheels without disturbing the others. The support H is pro- 
vided with two half boxes, h li\ one of which, A, serves to receive 
the cross-rod J", on which all of the supports II rest. The half 
box h' receives the journals of the toothed segment C, which is 
carried by the support H. It will be evident that with the 
parts so arranged any one of the segments and its support can 
be lifted out at pleasure and afford access to the wheel below. 
This arrangement is of much practical value, since in the 
machines as heretofore constructed the rod e7 passed through the 
supports H^ and the toothed segments were mounted on pins 
passing through them and secured in jaws formed on the ends 
of the supports, so that the whole had to be taken apart to 
replace a wheel. The supports are adjusted by means of 
set screws A^, so as to regulate the space between the toothed 
hubs of the wheels and the segments. 



480 



THE MANUFACTURE OF LEATHER. 



List of all Patents for Machines for Measuring the Areas of Hides, 
Skins, and Leather, issued by the Government of the United States 
of America, from 1790 to 1883 inclusive. 



No. 


Date. 




Inventor. 


Residence. 


194, S62 


Aug. 28, 


1877. 


M. V. B. Ethridge, 


Lynn, Mass. 


194,743^ 

Reissue V 
9,204 J 


Aug. 28, 
May 18, 


1877. 
1880. 


F. F. Tapley, 
C. H. Porter, 


Lynn, Mass. 

East Stougliton, Mass, 


208,942 


Oct. 15, 


1878. 


D. T. Winter, 


Peabody, Mass. 


215,853 


May 27, 


1879. 


D. T. Winter, 
r J. H. Williams, 


Peabody, Mass. 
Newton, Mass. 


218,802 


Aug. 19, 


1879. 


< S. Moore, 

I R. H. Hulburt, 


Newton, Mass. 
Sudbury, Mass. 


228,791 


June 15, 


1880. 


J. S. Wentworth, 


Lynn, Mass. 


231,741 


Aug. 31, 


1880. 


D. T. Winter, 


Peabody, Mass. 


256,058 


April 4, 


1882. 


W. A, Sawyer, 


Danversport, Mass. 


258,969) 
258,970) 


Jmie 6, 


1882. 


D. T. Winter, 


Peabody, Mass. 


269,962 


Jan. 2, 


1883. 


W. A. Sawyer, 


Danversport, Mass. 


281,745 


July 24, 


1883. 


C. G. Winter, 


Boston, Mass. 


286,078 


Oct. 2, 


1883. 


W. A. Sawyer, 


Danversport, Mass. 



PART VII. 

CHAPTEE XXYIII. 

SOLE LEATHER. 

Section I. General Eemarks. 

By sole leather in the broadest sense we understand a thick 
leather prepared by tanning heavy hides of oxen, heifers, and 
cows with any substance, either vegetable or mineral, that will 
change the nature of the hide so as to render it suitable for 
boots and shoes. 

In this country the materials generally employed for convert- 
ing hides into leather, are oak and hemlock barks ; when the two 
are used together, the leather is called " union tannage." 

In the manufacture of sole leather it is sought to combine the 
greatest possible amount of tannic acid with the hide, and this 
branch of the tanner's art requires the highest knowledge of the 
business. While in the production of upper leather as much 
depends upon the currying and finishing as upon the tanning, 
and in that variety of leather it is not sought to place the 
greatest possible amount of tannin in the hide. 

Oak-tanned sole leather commands the highest price in the 
market, which arises from a variety of causes. The coloring 
matter and resin imparted to the hemlock-tanned leather have a 
tendency to make it harder and more brittle, which militates 
against it in the market. On account of the better price obtained 
for oak-tanned leather, the producers of this variety are enabled 
to pay a better price for the choice of hides, thereby securing 
usually the best, and the extra price also allows greater care to. 
be exercised in the tanning and finishing of the stock. 

As far as the astringent principle of hemlock and oak bark i& 
31 



482 



THE MANUFACTUEE OF LEATHER. 



concerned there is no difference between them in their action on 
the hide, which cannot be truthfully said of the japonica and 
other highly concentrated tanning agents so enormously used 
in Great Britain. In commerce the hemlock-tanned leather is 
again graded into two classes, the better being styled as "hem- 
lock non-acid," and the lower grade as "hemlock acid;" but 
this is not, accurately speaking, a truthful descriptive division 
of the two processes commonly employed for accomplishing the 
"plumping" or distending of the hide for the reception of the 
tan liquor, as an acid is really used in both cases, the difference 
being that a vegetable substance (mostly gallic acid) is em- 
ployed in the first place, and sulphuric, a mineral acid, in the 
second. 

In this country sole leather is divided into the following 
varieties : — 



Hemlock. 



Buenos Ayres, light, non-acid ; middle 
weight ; overweight. 

California, light ; middle weight ; over- 
weight. 

Common hide, light ; middle weight ; 
overweight. 

Acid, all kinds, light ; middle ; heavy. 



Good damaged, all kinds and weights. 
Poor damaged, all kinds and weights. 
Prime export and jobbing leather, 

heavy. 
Calcutta buffalo, light ; middle ; heavy ; 

damaged. 



Oak Slaughter. 



Dressed backs, light ; middle ; heavy. 

Belting buts, rough. 

Bellies. 

Light Philadelphia and Baltimore 

tanned. 
Middle. 



Heavy. 

Louisville, no brands, X. 

A. 
Country tanned, light 
heavy. 



medium ; 



Oak Texas Hide. 

Good to best, middle and heavy i Common to good. 

weights. I Good damaged, best tannages. 



Light backs. 
Middle backs. 
Heavy backs. 
Damaged backs. 
Light crop. 



Union Slaughter. 

Middle crop. 
Heavy crop. 
Bellies. 
Heads. 



SOLE LEATHER. 483 

The sole leather which will be described in the next section 
is that known as "oak slaughter," and the process which we 
shall give, is that emploj^ed at the large and well-known tan- 
nery located at Luray, Va. The tan-bark employed is known 
as chestnut-oak, and the hides are derived from Chicago, 111., 
St. Louis, Mo., Memphis, Tenn,, Baltimore, Md., and Washing- 
ton, D. C. 

Section II. Tanning and Finishing Oak Slaughter 
Sole Leather. 

The hides are placed in the " soaks," in which vats of water 
they remain three or four days, the period depending upon their 
condition, the water being changed with each pack of hides. 

From the "soaks" the hides are carried to the lime vats and 
are changed each day by means of a reel into stronger lime, and 
in these vats the hides remain until the hair is loosened. They 
are next unhaired, and afterwards fleshed, and then thrown into 
a vat of clear water and left to remain over, night. 

In the morning the hides are removed from the clear water 
and "grained," which process consists in scraping the hides on 
the grain side in order to cleanse them more thoroughly from 
the lime remaining in the pores. 

After being "grained" the hides are again placed in clear 
water, where they remain for three or four hours, which com- 
pletes the beam-house work. 

The hides are next suspended in the "handlers," which opera- 
tion is the first stage of the tanning process. They remain in 
the handlers for about three weeks, the liquor being at first 
quite weak, but is changed each day upon the hides, being 
gradually made stronger. 

After being properly "plumped" the hides are removed from 
the handlers, and are placed upon a truck, and conveyed upon 
a tramway to the "lay-away yard," where the tanning process 
is completed. 

The " lay-away vats" measure nine feet in length, seven feet 
in width, and six feet deep, and in these vats the hides are 
placed one by one, spread out flat, and a thin laj^er of dry. 



484 THE MANUFACTURE OF LEATHER. 

ground bark is sprinkled over each hide, in order that the 
liquor may circulate uniformly. About eighty-five hides form 
a pack for each lay-away vat. 

After the hides have laid-away for a sufficient length of time 
to extract the tannin partially out of the "liquor," they are 
taken out and the liquor run off into a receiver through wooden 
pipes and pumped by steam power back to the leaches, where 
it passes through the bark and is restrengthened and then run 
as new liquor into the tan vats, and the hides are then put back 
as before. 

Each "pack" is usually " laid-away," ^. e., given new liquor 
five times, the whole operation of tanning extending over a 
period of about five months. 

From the "lay-away yard" the hides are placed on trucks 
and conveyed on a tramway to the scouring machine. 

The scouring machine used for this variety of leather is 
shown in Fig. 141 ; before the hides are scoured they are split 
into sides. Bach scouring machine will turn out one hundred 
and twenty- five sides of scoured leather per day. From the 
scouring machines the sides go into the drying loft, which is 
situated over the tanyard, and of course in a connecting build- 
ing with that in which they are scoured. The loft is heated by 
steam which circulates through a series of pipes connected with 
the boiler. 

In the loft the sides are suspended on sticks two by two 
inches and eight feet long, which sticks are partially rounded 
upon the edge that comes in contact with the side of leather. 

Two sides are suspended upon each stick about one foot 
apart, and a passage-way 6' 6" wide is maintained in the centre 
of the loft, and on each side of this passage-way two rows of 
sticks for holding the hides are placed. 

The steam pipes used for heating the loft are placed about 2' 
6" away from the outside rows of leather, and are attached to 
the upright studding and pass around the loft. 

In drying sole leather it is very desirable that too much light 
should not be allowed to enter the loft, as it is injurious to the 
color. 

Around the base of the drying loft the weather-boarding is 



SOLE LEATHER. 485 

hung ou hinges which can be adjusted to admit air without too 
much light; the windows in the loft admitting only sufficient 
light for the workmen. 

In the peak of the building are other openings so constructed 
as to be easily opened, and closed, thus creating a constant 
draft. The steam pipes are self-acting, and distribute heat more 
gently and uniformly than the old manner of drying with 
stoves. Experience has shown that the sides are the proper 
places to fasten the steam pipe, and the current of air from the 
outside is usually sufficiently strong to force the heated or dry 
air to the centre, and thus form a current towards the top open- 
ings. Without such openings the air forms a current up the 
sides of the building and does not reach the centre. The effect 
of side openings, other than the kind mentioned, is to create 
counter currents, thereby destroying the whole effect. With 
pipes for a circulation of steam properly arranged in connection 
with an intelligently constructed drying-loft, sole leather wet 
from the vats can be dried in forty-eight hours, ready for the 
roller. 

The sides of leather are not allowed to become entirely dry, 
sufficient dampness being allowed to remain in them for rolling, 
which operation is conducted in a building on a level with the 
drying-loft and opening into it, but in which a larger amount of 
light is admitted for the workmen than could be allowed in the 
drying-loft. 

The rolling machine shown in Fig. 225 is the kind generally 
employed for rolling sole leather. These machines are manu- 
factured by the Eureka Bark Mill Co. of Lancaster, Penn. 
The rollers on these machines are made of brass, and are six 
inches in diameter and six inches face or length, and are turned 
to a true surface and work into roller beds or concaves, which 
are also of brass and planed true to the radius or length of the 
vibrator or pendulum of each machine. 

The pressure of the rollers upon the leather is imparted by 
means of levers connected with the vibrator or pendulum of 
each machine, and controlled by a lever worked by the foot of 
the operator ; the hook to which the foot-piece is connected is 
shown in the drawing of the machine. 



486 THE MANUFACTURE OF LEATHER. 

A list of patents for rolling machines, including those used 
for sole leather, is given on page 467. 

After the roller has passed over a portion of the side two or 
three times it is shifted by the hands of the operator until all 
parts are successively operated upon. 

Fiff. 225. 




The side is then placed in the loft, and on the following day 
it is again rolled and hung in the loft, and when dried the sides 
of leather are ready for market. 

From the time that the green hides arrive at the tannery 
until the finished sides are ready for use, the time consumed is 
about six months, two processes of tanning being completed 
each year. 

Section III. Tanning Inside Sole Leather. 

The term inside sole leather, though very old, is by no means 
correct, since this variety of leather is chiefly used for soles of 
ladies' shoes, only the offal (head and sides), with exception of 
hides much punctured by the larvae of gadflies, which are not 
fit for any other purpose, being employed for the manufacture 
of inside soles. 

The mode of tanning this variety of leather is nearly the same 
as that of ordinary sole leather, the principal difference being, 



SOLE LEATHER. 487 

that the hides are seldom sweated, the hair being loosened bj 
liming. 

Dry hides are sometimes used, although thin domestic hides of 
cows and oxen, but weighing heavy, are generally employed for 
manufacturing inside sole leather. When green hides are em- 
ployed they are soaked for twelve to twenty-four hours, rinsed 
and freed from dung during this time, and placed, after final rins- 
ing and draining off, in weak milk of lime. Dry hides must be 
thoroughly soaked before placing them in the " limes." 

The hair of green hides, frequently handled, will become loose 
in from six to eight days, while about fourteen are required for 
dried hides. 

As soon as the hair can be easily pulled out depilating is pro- 
ceeded with. 

After being unhaired the hides are soaked for twenty -four to 
forty-eight hours with frequent rinsing, and then fleshed, which 
is done in the same manner as with sweated hides. After fleshing 
they are placed in a vat of water, fresh water being admitted 
every day and the hides handled tAvice daily. 

After six to eight days, according to the higher or lower tem- 
perature, scouring is proceeded with. In case the hides feel rough 
upon the grain side they are smoothed by forcibly driving the 
"stock stone" over the grain side, this being of advantage even 
if the hides feel entirely smooth. 

The hides possess a sufficient degree of softness when the 
ground and lime-slime is easily removed, and the impressions 
made by passing the fingers over them remain visible for some 
time. They are then placed in water for a few hours or over 
night, and finally brought into the " handlers." 

Inside sole leather can be raised in the liquors from which 
♦sole leather has been removed. 

The treatment of the hides in the handlers and the after-pro- 
cesses are the same as those described for hides intended for sole 
leather. 



488 THE MANUFACTURE OF LEATHER. 

Section IV. Bleaching Hemlock Tanned and Union 
Tanned Leather similar to Oak Tannage. 

This invention, which is that of E. W. Phillips, of "Waverly, 
N. Y., consists in bleaching hemlock-tanned and union-tanned 
leather similar to oak, and also has for its object to increase the 
percentage of leather from a given quantity of hides. 

To carry out this method proceed as follows: For fifty hides 
or one hundred hides, of average weight and tannage, prepare 
a mixture of five hundred and fifty gallons of pure cold water 
(soft water is the best), and six pounds of copperas, and suspend 
the sides or hides, if tanned whole, from rods in such a manner 
that they will be thoroughly immersed in the liquor, where let 
them remain for the period of thirty-six hours. The second step 
consists in removing the sides from the copperas-liquor and 
immersing them in a liquor composed by dissolving one hundred 
and fifty pounds of borax in five hundred and fifty gallons of pure 
water heated to 120° F., the sides being kept slowly moving in 
this liquor for the period of forty-five minutes, or until the 
leather feels slippery to the touch. In making the change into 
this liquor it it is best to put in at one time only so many sides 
or hides as can be convenientl}^ kept in motion for the period 
stated, after which the sides are removed from the borax liquor 
and immersed in liquor No. 3, which is a mixture of fifty pounds 
of oil of vitriol or sulphuric acid and five hundred and fifty 
gallons of pure water heated to 115° F., in which mixture the 
sides are kept moving for one and one-half minutes, or until the 
desired color is obtained, after which the leather is quickly 
removed from the liquor and placed in a pool of clear running 
water, where it is left until all trace of the liquor has been 
removed, when the process is complete and the leather may be 
hung up to dry. 

In making the change from the borg-x-liquor to the acid-liquor 
it is best to take only a few hides at a time, so that they can be 
quickly handled and not left to remain too long in the acid- 
liquor. 

After the number of hides or sides stated have been treated 
with the several liquors in the manner described, the old liquors 



SOLE LEATHER. 489 

should be thrown away and fresh ones made for the succeeding 
tannage ; or, if preferred, the strength of the spent liquors may 
be raised to the standard by adding a sufl&cient quantity of the 
ingredients from which they are made. In order to insure the 
best results the strength of the different liquors, as also the 
length of time during which the leather must be left in them, 
should be slightly varied according to the weight of the leather 
and the degree of tannage. This must be left to the judgment 
of the bleacher, though the formula herein given, if strictly fol- 
lowed, will produce substantially the results claimed on any 
weight or tannage of leather. For the several liquors soft water 
or rain-water is best, although not indispensable. 

In all the processes of union-tannage, light liquors are used to 
obtain the desired color, and consequently the weight is less 
than if heavier liquors could be used, and an advantage claimed 
for the process which has just been described, is that liquor of 
any required strength can be employed. 

It is claimed that an expert cannot distinguish hemlock and 
union-tanned leather finished by this process from clear oak- 
tanned leather. 

Section Y. Artificial Sole Leather. 

Large quantities of artificial sole leather are produced at 
"Woburn, Salem, Peabody, and other places in Massachusetts, 
from leather scraps obtained from the numerous tanning and 
currying establishments in those places, and sole leather thus 
produced is much used in Lynn and other shoe manufacturing 
centres of New England, as well as in Chicago and other western 
cities, in the manufacture of cheap boots and shoes. In the 
different State penitentiaries where boots and shoes are manu- 
factured, artificial sole leather is also much employed. This 
material forms the inside sole, and when it is used for heels one 
or two layers of good leather are nailed on the outside. 

The following process for making from scraps and waste an 
artificial leather impervious to moisture, and to be used for soles 
and heels of boots and shoes, was patented in most of the Euro- 



490 THE MANUFACTURE OF LEATHER. 

pean countries in 1882, and in the United States in 1883, by 
Emil Pollock, of Vienna, Austria-Hungary. 

In carrying this invention into practice, the leather scraps 
and waste to be used in the manufacture are first assorted, and 
those which had been dressed or treated with oil or grease sepa- 
rated from those not dressed with oil. The former are placed 
in a bath composed of ninety-five parts of water and five parts 
of soluble glass (potash or soda glass) of 35° Baume, or into a 
bath containing a proportionate quantity of soluble glass of 50° 
Baum^, as desired. The leather scraps or waste are allowed to 
remain in this bath, which may be cold or lukewarm, from one- 
quarter to one-half hour, according to the quantity of grease or 
oil contained in the scraps. The scraps are then drained off 
and placed in a solution of five parts of sulphate of zinc in five 
hundred parts of water. In this solution they are soaked for 
about half an hour. They are then pressed dry and ready for 
further treatment. In place of the soluble glass, any of the 
alkalies or any of the salts with alkaline reaction may be em- 
ployed, and in place of sulphate of zinc, any salt the base of 
which forms an insoluble combination with acids may be used. 
The so-prepared leather scraps or waste are now mixed with a 
paste that is formed by a thin solution of starch, to which solu-. 
tion, while in a boiling state, a small quantity of gum arable is 
added, and also to about twenty parts of the starch solution one 
part of a solution of alum consisting of five parts of water to 
one part of alum. The leather scraps are put into the starch 
and alum solution until they are thoroughly saturated. They 
are then, piece after piece, covered with a concentrated paste 
solution and placed in flat moulds in layers, one on top of the 
other, and beaten with hammers into sheets. The sheets thus 
formed are placed in a vessel containing a solution of soda soap, 
in the proportion of about one part of soda soap to two parts of 
water, and after having been well soaked therein they are sub- 
jected to hydraulic pressure, and finally dried, after which the 
sheets are ready for use. 

By the above process the oil and grease contained in the 
leather scraps are saponified, and the soluble soap transformed 
into an insoluble one, which dispenses with the removal of the 



SOLE LEATHER. 491 

grease from the scraps and produces the utilization of the grease 
in the formation of the insoluble soap, by which the leather is 
rendered water-proof. 

The following chemical reaction takes place in the process 
described : The sulphuric acid of the alum combines with the 
soda of the soap, while the stearic and oleic acids, 
/C,3H,g02, stearic acid,\ 
V CjgHj^Og, oleic acid, J 
which were combined in the soap with the soda, become free to 
enter into a new combination with the argillaceous earths of the 
alum, the hydraulic pressure favoring the most direct mechani- 
cal combination of the two salts. Consequently, the leather 
becomes thoroughly impregnated with sebate of alumina, by 
which it is claimed to be protected against moisture so as to be 
water-proof. 

When leather scraps which contain no grease or oil are em- 
ployed the saponification of the grease is dispensed with, and 
the scraps are mixed directly with the thin paste of starch and 
alum, and are then worked up with thick paste into sheets and 
treated in the same manner as the oil-dressed scraps, and finally 
exposed to hydraulic pressure, forming a tough, and as it is 
claimed, a water-proof leather that can be used extensively in 
the arts. 



492 THE MANUFACTURE OF LEATHEE. 



CHAPTER XXIX. 

HEAVY UPPER LEATHER — TANNING AND FINISHING THE "SIDE" 

- AND " split" — REMOVING EXTRACTIVE MATTER FROM TANNED 

LEATHER — PROCESS FOR WATER-PROOFING, DUBBING, AND 

V/HITENING UPPER LEATHER — IMPROVEMENT IN TAN PRESSES. 

Section I, Tanning and Finishing the " Side" and "Split." 

Under the head of upper leather are placed the soft and pli- 
able leathers which are employed principally, but notexclusivelj'' 
in manufacturing the uppers of boots and shoes. Upper 
leathers are produced from such hides and skins as Patna and 
East Indian kips, light and heavy cowhides, Buenos Ayres and 
Eio Grande hides, calf-skins, horse-hides, and split heavy hides. 
The processes of tanning and finishing are more rapidly com- 
pleted and less complex in proportion to the thickness of the 
hide treated, while at the same time, the percentage of tannin 
extract which the hide absorbs is likewise dependent upon its 
thickness. 

Lime is generally employed to soften the bulbous roots of 
the hair, and thus facilitate its removal by mechanical scraping 
with a blunt-edged knife or by machines constructed for that 
purpose, which have been explained in Chapter XVI. 

The lime used for upper leather must be removed in the 
preliminary stage of preparing the hide for tanning with 
greater thoroughness than is essential in the case of hides for 
sole leather ; and for this purpose the hides are subjected to 
various treatments and in addition go through the process of 
bating or " grainering." 

There is a great deal of obscurity surrounding the theory of 
the process of bating, but it has been explained on the suppo- 
sition that the uric acid of the hen dung employed removes the 



HEAVY UPPER LEATHER. 493 

excess of lime, and that the ammonia generated by tlie putre- 
faction of the mixture tends to form an ammoniacal soap with 
any remaining fat of the hide ; but as the gelatin of the hide 
exists in two states — one the principal, hard, or fibrous portion, 
and the other contained between the fibres, and which is more 
soluble and easily affected by agents and putrefaction — this 
softer portion is removed by bating, and the leather when 
tanned is light and porous, and more readily permeable by 
water, which is sought to be obviated by the subsequent stuf&ng 
of the leather with oil and tallow. In the preparation of most 
kinds of upper leather the heavier hides are split into two, and 
sometimes more portions. In the case of a single split the por- 
tions form a grain and flesh side; when three sections or slices 
are made they result in grain, middle, and flesh splits ; the minor 
splits from shoulders, heads, etc., will be explained in the prac- 
tical part of this chapter as they are reached during the progress 
of the hide into upper leather. 

Some tanners split hides in the green condition, others after 
coloring, and in some cases the splitting is done by the currier, 
as a regular part of his operations, after the leather is fully tanned, 
this being particularly the case with imported tanned East 
India kips, and other fully tanned leather of foreign origin. 

The fact that machinery is now largely employed by some 
tanners and curriers for nearly every mechanical operation, 
while others still adhere to the old system of manual manipu- 
lations of the hide and leather, will of course make it impossible 
for this chapter to apply to every case. 

Then, again, some manufacturers employ machinery at one 
stage of the operation, while others reject it at that point and 
use it at some other stage. The machines described are those 
only that from personal knowledge we know to be acceptable in 
many instances by prominent tanners and curriers ; the basis of 
description will be at Salem, Mass., and the manufacture of 
heavy quality of hemlock-tanned upper leather is that which 
we will consider. In the city of Salem, and its adjoining neigh- 
bor Peabody, is produced a large quantity of upper leather, the 
hides used being mostly foreign, but some domestics in all con- 



494 THE MANUFACTUEE OF LEATHER. 

ditions are also employed; they are kips, light cows, and heavy 
cows. 

A large number of hides have latel}^ been brought from China ; 
all the states of South America send hides to Massachusetts, 
east and west coast of Africa hides are also used, California hides 
are also employed, and Mexico sends them in moderate quantity, 
but South America furnishes the largest number. The bark 
used for tanning is usually hemlock, being derived mostly from 
Canada ; but Maine also ships hemlock bark in schooners, and 
it arrives in Salem in a less broken condition than that received 
from other localities. Pennsylvania also furnishes some bark to 
Salem, and extracts of bark are also employed there for tanning, 
but only in small quantities. 

In the State of Massachusetts the bark is nearly all bought 
by the cord, but some of the large tanneries purchase by weight. 

Preparation of the Hides, 

The hides first go into the " soaks" of clear cold water, and 
the period which they remain here is of course dependent upon 
the kind of hide, and varies from one to three weeks for those 
in a dry condition. Soft water is preferred for the " soaks" for 
upper leather, as the hides must not be swelled as much as those 
for sole leather, as otherwise the smooth cut would be injured. 

After they are split into sides, previous to which the hides 
are drawn into a pack, the hair side being placed uppermost, 
a knife is driven from the butt through the centre of the back. 
The sides are then placed in the hide-mill, which is a machine 
constructed similar to the fulling-mill used in woollen factories, 
and the time which they remain in the mill varies from one- 
fourth to three-fourths of an hour, the period being dependent 
upon their hardness or softness. Green salted hides are not of 
course worked in the hide-mill. 

From the hide-mill the sides are placed in clear cold water 
and remain over night, which period is sufficient if the first 
soaking has been properly done. Sometimes the sides are re- 
placed in the same water from which they were taken previous 
to going into the hide-mill, and this hastens the process of de- 
pilation ; but this results in loss in the end, as they cannot 



HEAVY UPPER LEATHER. 495 

develop into properly plumped leather, and of course do not 
give profitable splittings. 

From the last water thej are removed to the "limes," and 
there remain until the hair is well loosened, after which they 
are unh aired, and this operation is now done either by hand or 
machinery. The style of machine commonly employed in Salem, 
Mass., for unhairing, is shown in Figs. 100 to 104. 

After the sides are unhaired they are placed in clear water 
and on removal are "green shaved," which is the removal of the 
loose flesh from the hide. Then the heads are run through the 
splitting machine, and the sides are next placed in the drench, 
and are worked about eight or nine hours in the bate, which 
contains hen manure. The object of the bating, as has been 
explained, is to neutralize the lime, open the pores for the 
admission of the tanning liquor, and also to render the leather 
more pliable. Pure cold water will extract the lime from the 
hide, but it leaves it much rougher and harder to finish than 
when hen manure is used. 

After being removed from the bate the sides are placed in the 
wash- wheel and worked for about fifteen minutes. The drench- 
wheels and wash-wheels are shown in Fig. 112. 

The period which the sides remain in the bate depends upon 
their thickness, the temperature of the bate, and the season, 
usually longer in winter than in summer. The sides then go to 
the hide-working machine, and here they are freed from lime 
and dirt, and are next thrown into clear spring water, where 
they remain over night. 

The style of hide-worker employed has an eccentric motion, 
and is shown in Figs. 114 and 115. The hide has thus, bv these 
preliminary operations of removing the portions not required 
for use and the cleansing, been prepared to receive and absorb 
the liquor in which the tanning matter is dissolved. 

Tanning. 

The sides are now placed in the handling liquor, which is a 
weak mixture, and remain in it for ten or twelve days for 
heavy upper leather, and during this period they are hung on 
sticks in the vats, and are afterwards twice " laid-away" in 



496 



THE MANUFACTURE OF LEATHER. 



ground bark, both lay-aways usually extending through a 
period of about two months, the first lay-away being for ten 
or twelve days, and the second consuming the remainder of the 
period. When removed from the lay-away the sides are hung 
on poles in the drying yard for a day to harden, and are then 
brought into the cellar and dampened. Fig. 226 shows the sides 
of leather hung over the poles, in the drying yard facing the 
finishing shops. The sides are next split. A day's work for one 
man on the union machine is about two hundred sides of leather. 
The operation of splitting the sides for upper leather consists in 
reducing them to a uniform thickness. 

Fig. 227. 




When the belt knife machine is employed the entire surface 
of the side is passed through in one operation, but the union 
machine usuall}^ requires two operations. The split is used for 
the tops of shoes or backs of boots, the splits are carried to a 
table and trimmed, which is the lopping ofi' of the rough edges, 
and they then follow the other leather through the process of 



HEAVY UPPER LEATHER. 497 

tanning. The shoulder is also passed through the splitting 
machine ; but the shaving is not tanned, and is sold for stiffen- 
ing stock, and is also largely used in cheap or shoddy shoes by 
what are termed " pan-cake shops," which are places where 
boots and shoes are made for looks more than for wear, though 
the better part of these skivings are used for stiff'enings and the 
lighter ones for "insoles." The splitting machine, etc., are 
shown in Fig. 119, and are described in detail in Chapter XX. 
The sides next go to a " flatter," who levels off" the shanks and 
bellies with a currier's knife, as shown in Fig. 227, and they are 
then carried to the tanyard, and placed in a revolving wheel to 
be softened, twenty-five sides being placed in the wheel at one 
time and moderately strong gambler liquor poured over them, 
and in this wheel they are milled for about ten minutes. 

The result sought to be attained in placing the sides of leather 
in the mill after they have been split is to prevent the " glazing" 
or "crusting" of the raw parts from which the split has been 
taken. They next go back into the handlers and are drawn 
each day, and the liquor renewed ; they are not hung upon sticks 
in the handlers this time, the sides being pressed down and the 
liquor allowed to flow over them, and the period which they 
remain here is about fifteen days. 

Finishing the Side. 

From this last liquor the sides are carried to the shop and 
scoured, which may be accomplished by hand, as is shown in 
Fig. 137. The machines employed for this work, as has been 
stated, are the Burdon Scourer, the Fitzhenry, and the Lock- 
wood, each of which is fully described in Chapter XXI. From 
the scouring machines the sides are again taken to the poles or 
yard shown in Fig. 226, for hardening, and from thence are 
carried into the cellar to be dampened, about two days being 
occupied in the tempering. 

They then go into the stuffing wheel, as explained in Chapter 
XXII., and the sides remain in the wheel for about fifteen min- 
utes, the grease being here driven into the leather by heat. Fifty 
pounds of grease are used to two hundred pounds of leather, i. e., 
for heavy upper leather ; boot leather requiring a greater quan- 
32 



498 THE MANUFACTURE OF LEATHER. 

tity of grease, the leather must be warm and be kept warm uni- 
formly during the time the grease is being applied to it. 

The stuffing wheel in operation at the establishment of Thos. 
E. Proctor, located at Peabody, Mass., seems to do this work 
more thoroughly than any other that has been inspected by the 
author. This stuffing wheel is shown in Figs. 160 and 161. 

The leather, after being removed from the stuffing wheel, is 
then set out on the improved Fitzhenry or Lockwood machines, 
which have been illustrated and described in Chapter XXI. 

The number of sides of heavy upper leather which can be set 
out on the improved Fitzhenry machine is about two hundred 
and seventy-five per day ; but three hundred and twenty-five 
sides of lighter leather can be set out by the machine in the 
same time. 

The next step in finishing upper leather is that of whitening, 
which process can be performed by going over the leather on a 
table with the slicker, or the surface can be cut over with a 
currier's knife, or the whitening can be done by a machine, 
improved forms of which are shown in Chapter XXIII. 

The leather is then "stoned out" on a jacking machine, and 
if it requires softening it is next boarded by a machine, as 
shown in Figs. 177 to 182. 

The sides are now carried to the blacking loft and the flesh 
side is there " blacked" with soap blacking. This flesh blacking 
is made in two ways, sometimes with lampblack and soap, and 
at other times with lampblack and oil. When " soap blacking" 
is employed, oil is very freely applied afterwards in order to 
fasten the color and body of the black. 

It is claimed for soap blacking that it fills the flesh with a 
better body and hides defects in the leather which show through 
if oil and lampblack alone are employed. For other blacking 
compounds, see Chapter XXY., Section II. 

The disadvantages urged against soap blacking are that when 
this leather is crimped for boots, the blacking washes off leaving 
a coarse surface, while the alkali contained in the soap will, if 
allowed to lie for some time, neutralize the grease, thus impart- 
ing to the leather a harsh feeling ; pure oil blacking, on the 
other hand, will gradually grow softer with age. 



HEAVY UPPEE LEATHER. 499 

Soap blacking is not now much used in foreign countries, and 
it is only used by us in the modified form to whicli attention 
has been invited. 

The blaclving is applied with a wet brush and thoroughly 
rubbed into the leather with a dry brush in the hands of the 
workman. 

There are machines for performing this work, as shown in 
Figs. 185 to 196 ; but they are not thought to answer so well 
for heavy upper leather as for softer and lighter leathers. 

The next operation is that of glassing, and this can be done 
either by hand or machinery, and when performed by a machine 
the same style is commonly employed as is used for rolling, 
pebbling, and finishing leather, but the improved Lockwood 
and Fitzhenry machines are also used. 

The Martin machine is largely used for glassing upper leather, 
and it is shown in detail in Figs. 200 to 203. 

After the side has been " tempered" it is again glassed, and 
then " pasted." 

Flour paste is used for the last operation, which is made from 
flour, with soap added, say in the proportion of about two pounds 
of hard brown soap to every pail of flour used, the soap being 
boiled with the paste. A piece of tallow about the size of an egg 
and a small piece of wax are also added to each pail of flour and 
also boiled with it. 

This composition is to " fill" the leather and make the stock 
"fine." 

After the leather is " pasted" it is dried and then " glassed in 
paste," which operation is also usually performed by the Martin 
Glassing Machine. 

The side is next " sized" with a preparation of gum paste 
applied to the flesh side with a sponge in order to finish. 

The " size paste" is made by dissolving four ounces of pure 
glue in warm water, adding a small piece of tallow, say half an 
ounce, and then diluting with water until the desired consistency 
is reached, when it can be easily spread with a sponge. 

After the application of the size the leather is hung up and 
dried, then assorted and finally measured, marked, and' bundled 
for market. An interior view of the finishing room of an upper 



500 THE MANUFACTURE OF LEATHER. 

leather manufactory showing the pasting tubs and tables, horses 
for receiving and moving the leather and the blacked and 
pasted sides suspended from hooks in the ceiling racks, is shown 
in Fig. 228. 

There are several ways for measuring leather. The old style 
measuring frame is still largely employed ; but later inventions 
for measuring leather are illustrated and explained in detail in 
Chapter XXYIT. 

Finishing the Split. 

There are two processes for stuffing the split: if hand stuffed, 
it is taken from the scouring machine and stuffed; but if wheel 
stuffed it is handled about the same as the grain, after which it 
is struck out, dried, whitened, and trimmed. 

There are also two methods for finishing a split : if a flesh 
split it is whitened on the flesh side ; but if a waxed split it is 
finished on the split side. 

No preparation is applied to the back of the flesh split, it be- 
ing left plain; but the waxed or colored split is stained on the 
flesh side, and it is strictly known as the "colored pebble," of 
which there are two colors, the oak and hemlock, the first being 
a yellow and the second a red. 

The process of "fitting" the colored split is as follows: — 

1. Coloring. 4. Grlassing. 

2. Drying. 5. Pebbling. 

3. Boarding. 

The machine shown in Figs. 206 to 208 is largely employed 
for the last-named operation. 

After pebbling, the colored split is ready for the "blackers," 
and the process from that stage is similar to finishing the "side," 
which has already been described at length. 

Head's Process for Soaking, Limi^ig, Tanning, Blacking, and 
Gumming Hides Intended for Upper Leather. 

Head's process is as follows : — ' 

The first step consists in soaking the hides, as they are re- 
moved from the animal, in a vat of water about eight feet long. 



IS 



00 s= 



•73 



^ =^ 




HEAVY UPPEK LEATHEE. 501 

four feet wide, and four feet deep, into which has been poured 
a mixture of one-half pound of saltpetre, one pound of potash, 
one pound of oil of vitriol, and twenty pounds of rook salt. 
This solution preserves the hides from decomposition, prevents 
the gelatine from dissolving, and assists in the liming process. 
Thej remain in soak from one to two hours. 

The second step consists in fleshing the hides after tliey have 
been soaked. 

The third step consists in placing the hides in a vat of water 
of about the dimensions given above, into which has been 
poured a mixture of one bushel of quicklime and one and one- 
half pounds of sal-soda. By the use of this mixture it is claim^ed 
that the time necessary to lime the hides is shortened to about 
six hours. This solution rapidly reraoves the albuminous sub- 
stances which hold the hair. 

After the hides have been taken from the lime above described, 
they are ready for the fourth step, which consists in soaking 
them in a vat of water at a temperature of about 110° F. They 
are allowed to remain in this vat about two hours, though a 
shorter time will accomplish the purpose as well. 

The fifth step consists in removing the hair and lime-shaving 
the hides. 

The sixth step consists in scouring them upon the grain side 
to remove all foreign substances, and prepares them for the color- 
ing liquor. It is seen that after the hides have been lime-shaved 
they are not placed in a bate, as is usually done, but are imme- 
diately scoured. This method, it is claimed, prepares them for 
the tan better than the process in common use. 

Seventh, the hides are placed in the coloring liquor, and re- 
main until they have acquired the desired color, which can be 
ascertained by watching them, and when removed from this' 
liquor the hides are immediately scoured, which removes all 
sediment and unnatural grain, and constitutes the eighth step of 
the process. 

Ninth, the hides are spread out on a table or floor, and the 
tanning solution well rubbed in with a brush or swab, and then 
laid away in a pile, which is the tenth step, the time which they 
remain in the pile being from two to fifteen days, according to 



502 THE MANUFACTURE OF LEATHER. 

the character of the leather to be tanned. While in the pile 
the hides are handled once a da}^ or oftener, more of the solu- 
tion applied, and the hides returned to the pile. If, however, it 
is desired to retain the color upon either side of the hide, the 
tanning solution is applied to the opposite side from that upon 
which the color is to be retained, the solution is well boarded in 
upon that side, the hides folded together separately with the 
side which is to retain the color outward, and replaced in the 
coloring solution. If it is desired to retain the color upon both 
sides of the hide, the tanning solution is applied to both sides, 
is well boarded in, the hides spread out flat, and returned to the 
coloring liquor. The hides remain in this liquor from two to 
fifteen days, according to the character of the leather to be 
tanned. While undergoing this process the hides are handled 
once or twice a day, scoured, more of the solution applied, and 
returned to the liquor. 

The eleventh step, which consists in " sammying" the hides, 
is then carried into efiect. 

The twelfth step consists in scouring them on both sides, the 
thirteenth step in setting them out on a table or floor and flat- 
tening them with a slicker, and hanging them up to dry. 
When the hides have become dry they are taken down, placed 
upon a table or floor, and stuffed, which constitutes the four- 
teenth step. 

The fifteenth step consists in packing the hides down in a 
pile and covering them up to protect them from currents of air 
and from the light, which allows the stuffing to penetrate them 
without injury to the color. The length of time the hides re- 
main in the pile is optional, though the shortest time necessary 
to obtain good results is two hours. 

■ The sixteenth step consists in dipping the hide singly in a 
vat of water at a temperature of about 120° F., which com- 
pletely drives in all the stuffing previously applied. After the 
hides have been dipped they are immediately struck out and 
hung up to dry, which is the seventeenth step. 

The eighteenth step consists in whitening, trimming, and 
boarding them after they have dried, and by which they are 
made ready for the blacking. 



HEAVY UPPER LEATHER. 503 

The nineteenth step consists in blacking the hides, and the 
inventor does this with a composition of one pound of Limp- 
black, one and one half pounds of Babbitt's soap, boiled together 
in three gallons of water. The advantages claimed for this 
composition are that it softens and improves the texture of the 
leather, or, in other words, makes it " mellow." It is claimed 
that Babbitt's soap gives the best results for this purpose. 

The twentieth step consists in smutting the hides off and 
applying oil and gum tragacanth to them. 

The twenty-first step consists in glassing them down and 
hanging them up to dry. 

The twenty-second step completes the process, and consists in 
gumming them off with clear gum tragacanth after they have 
dried. 

Section II. Eemoving- Extractive Matter from 
Tanned Leather. 

In 1879 Plumer and Kernans, of Peabody, Mass., patented 
the following process for removing extractive matter from 
tanned leather: By this method leather tanned by the hemlock, 
oak, or other usual processes is subjected to a cleansing bath, 
which removes the extractive and tanning substances, grease, 
tannate of lime, etc., added to»the hide during the liming, bat- 
ing, and first tanning processes ; especially such matter as 
would tend to make the finished leather hard, or brittle, or 
which would interfere with giving to the grain-face of the 
finished leather a lisfht. even color. This the inventors claim 
to accomplish in the following manner: The tanned leather, 
say, twenty-five sides, containing from twenty to twenty-five 
feet each, are subjected in a mill to the action of diluted solu- 
tion of borax for from ten to fifteen minutes ; for the quantity 
of leather mentioned about six pounds of borax are dissolved in 
about thirty gallons of water. 

In practice the best results are obtained by the use of a closed 
circular or box-like wheel of about eight feet diameter bj^ two 
or three feet in width, and having a hollow journal for the en- 
trance of a water or steam pipe, and a side door for the intro- 



504 THE MANUFACTURE OF LEATHER, 

duction and removal of the leather, the door to be suitably 
packed to obviate leakage. 

Having added the borax-water to the wheel, and placed the 
tanned leather therein, the wheel is rotated at tlie rate of about 
sixteen revolutions per minute for about fifteen minutes or until 
the objectionable matters referred to are loosened, when a hose 
or other water supply pipe is added to the hollow journal of the 
wheel to lead water into it, and in contact with the leather, so 
as to wash out the borax and other matters loosened or started 
by the first milling operation in the borax water. This treat- 
ment, it is claimed,, leaves the leather in proper and the best 
possible and most favorable condition to be retanned for all 
leather where softness and lightness of color are desired. 

Section III. Processes for Water-proofing, Dubbing, 
AND Whitening Upper Leather. 

Eady patented the following process for water-proofing, dub- 
bing, and whitening upper leather, the object being to give the 
leather a "satin finish." 

The process is as follows : A rough-tanned skin is first 
soaked, shaved, scoured, and then retanned, and next scoured 
and dubbed with oil and tallow, and then whitened, after which 
it is water-proofed by the following process — which is the first 
point of the combination where this invention commences. 

For the first p^art use a compound which consists of one part 
of dry gelatine (isinglass or other) dissolved in four parts of oil 
including a small quantity of sulphuric or other acid, and, when 
these are combined by means of heat, five parts of an alkaline 
solution are added, at a specific gravity of about 26"^ Baume, 
the whole being stirred while yet warm, and the result is a 
chemical combination designated as "the preparatory com- 
pound." 

For the second part of the process use the compound which 
is designated the "perfecting compound," prepared as follows: 
In one vessel prepare a strong solution of one of the alums 
(for instance, of the sulphate of alumina) with potassa, ammonia, 
or soda. In another vessel prepare a solution of the sulphate 



WATER PROOFING UPPER LEATHER,' ETC. 505 

of zinc, and in a third vessel a solution of the acetate of lead. 
These solutions are each to be of the same density. When pre- 
pared, the two sulphate solutions are mixed in the proportions 
of about five parts of the first to one and a half parts of the 
latter, and to these are added about five and a half parts of the 
acetate-of-lead solution. By the chemical action that ensues 
sulphate of lead is formed, and when this has subsided the clear 
liquid is drawn off, and is reduced to the proper density, which 
is from 1° to 2° Baume, 

The manner of treating the material to be water-proofed is as 
follows : A bath is prepared with half an ounce of the prepara- 
tory compound dissolved in two gallons of hot water — that is, in 
about these proportions — and is used when cold. To treat leather, 
steep it in this bath till indued with its properties, and then 
drain it ; or the preparatory compound may be dissolved to 
about the consistency of cream, and then applied by hand before 
the "stuffing." 

Boots, shoes, and harness are treated before the final finish. 

The second part of the process is conducted as follows : When 
the goods have been removed from the preparatory bath, and 
are well drained, steep them in a bath of the "perfecting com- 
pound," where they remain from eight to twelve hours, and 
when well drained, they are gradually dried, which completes 
the water-proofing. 

After the water-proofing the side or skin is dubbed with tallow 
and oil, after Avhich it is whitened, and then finished. 

The final combination of dubbing, whitening, water-proofing, 
etc., it is claimed, gives -the leather a superior finish. 

S'ponhouse's Method for Manufacturing Water-proof Leather. 

In the selection of hides take those which are dry, as green 
hides are more porous. A solution of lime is made, care being 
observed not to make it too strong, for if too much lime is used 
it will swell the leather, and thus render it porous, soft, and 
spongy. The leather is then placed in the solution, as ordi- 
narily, and when all animal or extraneous matter has been ex- 
pelled therefrom, it is bated low in the usual manner with the 
proper decoction, in order to extract the lime as clean as 



506 THE MANUFACTURE OF LEATHER. 

possible, so that the tannin will penetrate it. The upper leather 
and kip hides are handled in sweet liquor only, as sour liquor 
will swell them. When about three-fourths tanned, the leather 
is shaved and thrown into sour liquor and allowed to remain 
for a week. The leather during that time is handled everyday, 
and taken out and scoured a little, after which the flesh side is 
stuffed with dubbing applied milk-warm, composed of the fol- 
lowing ingredients: Tanner's oil, 4 parts; flaxseed oil, 1 part; 
tallow, 2 parts; care being taken not to staff the leather too 
thick or heavy with the dubbing. The leather is then folded 
up tightly and put into a close box and allowed to remain for 48 
hours, so that the stuffing will enter the pores. A strong solu- 
tion of bark is made in a vat, in which the leather is then 
placed with the flesh side down, in order that the solution will 
tan in from the grain side. By this operation the stuffing and 
the oil will be tanned with the leather. It is then permitted to 
lie in the vat about 6 weeks, when it is taken out and scoured 
and allowed to get about half dry. The following ingredients, 
with the proportions of each given, are then mixed and applied 
milk-warm to the leather, viz: tallow, beef or sheep, 1 pound; 
tanner's oil, IJ pounds; beeswax, 3 ounces; castor oil, 4 ounces. 
The leather is then again tightly folded and put into a close Vjox 
and allowed to remain 48 hours. The same dubbing, composed 
of the above ingredients just mentioned, is stuffed on the grain 
side for wax finish, and the same again applied on the flesh side 
for grain finish, pure tanner's oil being used for this side. For 
the finish, or blacking for wax finish, take lampblack, one 
pound, and apply dubbing again on the grain side. The follow- 
ing ingredients are mixed with those herein above described, viz : 
beef gall, 1 ; India rubber, IJ ounces. Oil enough is added to 
make the same of the proper consistency. The rubber must 
not be dissolved in alcohol or spirits of turpentine, as it will 
injure the leather, but cut into strips and ignited, and the oil 
collected therefrom used. In the dubbing this will make a fine 
finish. 

The ingredients herein described, and as combined in the 
manner in which they are used and applied in the process of 
tanning, constitute Sponhouse's water-proof composition for 



TAN PRESSES. 



507. 



leather. The composition is applied the same as other blacking 
to a boot or shoe, and will not only give a fine polish to it, but 
keep it soft and pliable, so as to make it easy for the foot. 



Section IV. Improvements in Tan Presses. 

In the present state of knowledge on the subject it may ap- 
pear idle to speak of the economy of a tan-press over drying the 
spent tan in the sun, or on the top of a boiler, or having it carted 
away as waste. By means of an elevator, consisting of buckets 
on an endless belt, the spent tan is taken from some convenient 
depository near the vats to a bin above the tan-press ; it feeds 
itself through, and is from there deposited in front of the boiler, 
where it is ready to be burned, thereby saving all labor except the 
little of getting the tan to the place where it is first taken up 
by the elevator. Thus there is obtained a good fuel convenient 
for use at almost no cost. 

Fig. 229. 




The furnaces in sole-leather tanneries are usually so con- 
structed as to burn wet spent tan ; but in upper-leather tanneries 
the material has to be treated so as to have it as dry as possible. 

The tan-press shown in Fig. 229 is manufactured by the 
estate of Charles Holmes, Boston, Mass., in two sizes, one size 
having 36 inch rollers and the other 28 inch rollers, the speed 
being about 165 revolutions per minute. This machine will 



508 



THE MANUFACTURE OF LEATHER. 



press from 15 to 18 cords of spent tan in ten hours, witli three 
horse power, and leave the material sufficiently dry for fuel. 

Fig. 230 shows a perspective view of the W. K. Daniels tan- 
press, which is manufactured in Salem, Mass. This press is 
made in two sizes, the smaller of which will press eight cords of 
spent tan in ten hours, and the larger, twelve cords. 

Fis. 230. 




Fig. 231 is a central vertical longitudinal section of the tan 
press invented by Thomas F. Weston, of Salem, Mass., and 
which is commonly known as the " Salem Tan Press." Fig. 232 
is a front view of the forward rollers of the same. 

The gearing and driving-wheels are not shown in the draw- 
ings, as any arrangement of well-known mechanism may be 
adopted for rotating the several rollers as desired. 

A represents the frame of a machine, having on each side a 
forward, upright, slotted, or open standard, B, provided with 
suitable boxes, or otherwise arranged to receive and allow the 
rotation of the axles or ends of an upper pressure-roller, (7, and 
an under delivery-roller, D, provided with suitable gearing or 
other mechanism for rotating them in contrary directions with 
eath other. Provided with suitable gearing, or otherwise 
arranged to rotate in the same direction with the delivery-roller 
Z), is a feed-roller, .£/, the ends or axles of which turn in boxes 
connected with the sides of the machine. The roller J5'is located 



TAN PEESSES. 



509 



at a sufficient distance in the rear of and below the forward pres- 
sure-roller C to leave adequate space to receive the tan, and at 



Fiff. 231. 




Fig. 232. 




a sufficient distance from the upper rear portion of the delivery- 
roller Z), and rotating in the same direction with it is a supple- 



510 THE MANUFACTURE OF LEATHER. 

mentary smaller roller F; between each roller i'^ and the pressure- 
roller G is left a sufficient space for the passage of the tan. 

The space between the feed and delivery rollers being filled 
bj the supplementary roller F prevents the falling through of 
the tan or other material, which is assisted in its passage and 
pressed against the pressure-roller G by the rotation of the roller 
F^ which is arranged to turn in the machine, and is provided 
with a gear-wheel meshing with the gearing operating the feed- 
roller E^ or otherwise provided with suitable mechanism for 
rotating it in the same direction with the said roller E. The 
gearing or other operating mechanism may be arranged to be 
actuated by steam or other motive power. The pressure-roller 
(7 is arranged to have a vertical movement in the standards B^ 
regulated by rubber or other suitable springs Q^ adjusted by 
screws ZT turning in the heads of the standards B ; or the pres- 
sure-roller G may be otherwise arranged, as desired, to have a 
yielding bearing or movement, or to be adjusted to admit of its 
operation on different thickness of material or matter. Any or 
all of the rollers may be corrugated or plain on the periphery, 
as desired. Z is a driving-shaft, and J a shaft carrying gear- 
wheels meshing with suitable gearing, operating the several 
rollers to carry the same in the direction required. 

The pressure-roller C is formed at each end with a lip, c, curv- 
ing up from the periphery of the roller to the rim of the lip, as 
shown, to close the space between the rollers G and D at the 
ends, and compress the tan or other material at the corners of 
the roller, so as to fill up the same and prevent the passage of 
liquid at these points, which passage is otherwise often apt to 
occur, owing to the tan not properly filling in at the ends of, as 
it feeds to, the roller. 

The operation of this machine is as follows : Power being 
applied to revolve the rollers, the tan is deposited at the top 
between the pressure-roller G and feed-roller E^ and carried 
between them, forming a sheet, which is taken by the supple- 
mentary roller F^ and carried along and against the pressure- 
roller (7, which presses it upon the feed-roller E^ between which 
rollers it is passed and delivered from the machine through a 
hopper, or into a receptacle, or as desired, comparatively freed 



GEAIISr SPLIT AND BUFFED LEATHERS. 511 

of liquid, the supplementary roller F^ turning snugly between 
the rollers E D^ preventing the passage of the tan between the 
rollers, and assisting in its passage and pressure, and the lipped 
formation of the roller ends c preventing the back passage of the 
liquid, as will be readily seen by the above description, and on 
examination of the drawings without further explanation. The 
liquid expressed from the tan flows downward between the small 
roller F and rollers E D into a suitable receptacle, the narrow 
space between said rollers allowing the passage of the liquid, 
but not of the tan. 



CHAPTBE XXX. 

GRAIN, SPLIT, AND BUFFED LEATHERS — TANNING AND FINISHING 
GRAIN SPLIT AND BUFFED LEATHERS — COMPOUNDS FOR PRO- 
DUCING IMITATION OF GRAIN AND MOROCCO LEATHER. 

Section I. Tanning and Finishing Grain, Split, and 
Buffed Leathers. 

The above varieties of leather are produced in large quan- 
tities in this country, "Woburn, Mass., being one of the chief 
centres for their manufacture. 

The bark used at that place is hemlock, and is derived from 
Canada ; the sumach employed is both imported and native. 

The hides used are chiefly green salted, and are obtained from 
St. Louis, Mo., Cleveland, Dayton, and Cincinnati, Ohio. Boston, 
Mass., and other points in New England furnish a few hides, but 
the supply from the latter sources is small. 

The hides used for the varieties of leather under consideration 
are " buff hides," i. e., those obtained from cows, heifers, and 
steers, and weigh about 50 lbs. each. 

The first step in preparing them for the tanning liquor is to 
place the hides in the " soaks" of clear, cold well water, and here 
they usually remain for four days. 



512 THE MANUFACTURE OF LEATHER. 

After being removed from the soaks, the hides are split into 
sides in the same manner as has been described for heavy upper 
leather, and after being split the sides are placed in the " limes," 
where they remain for six days, being reeled into a vat of 
stronger lime each day. 

The sides are next unhaired, which is accomplished both by 
the hand and -machine process, one hundred sides being a day's 
work for one man by the first method, while eight hundred 
sides of leather can be unhaired by two men in one day of'ten 
hours by the machine method. 

When unhaired by machinery the sides are passed through a 
McDonald or other suitable unhairing machine, and are then, 
by some large manufacturers of these varieties of leather, 
thrown into a vat containing sulphuric ac'd diluted with water, 
from which they are immediately dipped out by an oscillating 
framework of wood, the time which the sides remain in this 
dilute sulphuric acid bath being not longer than one minute. 
The sides are then passed through a second McDonald or other 
suitable unhairing machine, and any hair that may still remain 
upon the edges is dressed off' on a beam with an unhairing knife 
by a workman. 

In this way eight hundred sides are unhaired in a day, and 
the wages of six workmen are saved. The unhairing machines 
are fully explained and illustrated in Chapter XVI. 

When the sides are unhaired in this manner by machinery 
and subjected to the dilute sulphuric acid bath, as soon as they 
are dressed off" by hand at the unhairing beam, they are thrown 
into a vat containing clear, cold, spring water. 

After remaining in this cold water for a short time, the sides 
are removed, and tacked to sticks and placed in the " handlers." 

This seems to be pushing things a little too rapidly, but the 
method is pursued by some of the largest manufacturers of 
buffed leather in the State of Massachusetts, who appear to have 
difficulty in making sufficient leather to meet the demands of 
their trade, while other manufacturers, who give more care to 
the stock which they produce, find it difficult in competing for 
a market. 

There is no doubt that a much larger quantity of lime is 



GRAESr SPLIT AISTD BUFFED LEATHERS. 513 

removed from the sides by passing them through the unhairing 
machines, which also scoar the sides, than conld possibly be re- 
moved by hand. Whether it is good policy to hasten the pre- 
paration of the side by the method which has been described, is 
of course not the province of this volume to decide, and should 
be settled by each tanner to his own satisfaction, taking indi- 
vidual experiences as a guide. 

Our large home consumption of leather and our constantly 
increasing export trade make it imperative to take advantage 
of every oportunity to hasten the production and lessen the 
price of this material, when it can be done without serious in- 
jury to the quality. If the method of unhairing by machinery 
and then subjecting the sides to a bath of sulphuric acid diluted 
with water, and then placing the side in cold water as described, 
answers all the requirements, then we think no objections should 
be urged against it. 

But to return to the point of divergence : After the sides are 
iinhaired by the hand process they are placed in a bate of hen 
manure in which they remain from twelve to thirty-six hours, 
but when the sides are worked in the bate with the England 
wheel shown in Fig. 112, the bating can be accomplished in six 
to eight hours, the time depending upon the weight of the hide 
and other circumstances, the object of the bate being to fully 
neutralize the lime, thereby allowing a smoother finish' to be 
applied to the leather. 

After being removed from the bate the sides are allowed to 
remain over night in a vat of clear, cold spring water, and are 
tacked to sticks and suspended in the '' handlers" containing 
hemlock liquor, which is increased from about 6° strength at 
the start to 12° strength at the finish. The sides are treated in 
these handler vats for about twenty-four days, being shifted 
every third day into stronger liquor. 

After being removed from the sticks they are hung over 
poles and dried in the open air, as shown in Fig. 226, and are 
next carried into the shop and skived usually by a belt- knife 
machine shown in Figs. 132 to 135 ; one man being enabled by 
means of a machine of this character to skive 400 sides in one 
day of ten hours. After being "fitted" or trimmed on a table 
33 



514 THE MANUFACTUEE OF LEATHEE. 

with an ordinary shoe knife they are next " split" usually by 
the same kind of belt-knife machine which has been mentioned. 
Two men will split 400 sides in one day of ten hours. About 
4| ounce grain to the square foot is usually taken off the side 
in splitting it. 

The " split" is then trimmed by hand, and placed back in 
liquor of about 8° strength, which is gradually increased, and 
remains for from twelve to fifteen days. 

The part from which the " split" is taken, called the " grain," 
is shaved on a beam with a currier's knife in order to make the 
side of uniform thickness. One man will shave from 60 to 70 
sides in a day, the number depending upon their size and con- 
dition. 

They are then " milled" with sumach liquor for about one 
hour in a revolving drum, which is commonly about seven feet 
in diameter. 

The sides are then placed in sumach liquor of about 8° 
strength, which is gradually increased, and remain for about 
sixteen days. 

For these leathers the American and Sicily sumachs are not 
mixed, as for Morocco leather, but are usnally employed 
separately. 

After being removed from the liquor they are next scoured, 
which is done either by hand or machinery ; if done by hand 
they are placed on a slate table, as shown in Fig. 137, and scoured 
first on the flesh, and then on the grain side. The tools used in 
this operation are the ordinary scouring brush, slicker, and stone, 
and by this method one man will scour fifty sides in a day. 

After being scoured, they are hung over poles and exposed to 
the air to harden, and are. then carried to the shop and stuffed 
in a revolving drum, such as has been explained and illustrated 
in Chapter XXII.; the operation of stuffing lasting for about fif- 
teen or twenty minutes. 

Fish oils, paraphine, oleine, and rosin are employed in the 
stuffing compound used for the "grains," and tallow, fish oils, 
and rosin for stuffing the " splits." 

The sides are next " set out," and after that are carried to the 
finishing-room and blacked on the grain side with a preparation 



GRAIN" SPLIT AND BUFFED LEATHEES. 515 

of logwood and copperas for the " grains," lampblack and soap 
being used for the " splits." 

The "splits" are immediately "glassed" on a machine such as 
is shown in Fig. 199, and then placed on a horse for convenience 
of moving to the hanging up hooks, as shown in Fig. 228. One 
boy of nineteen or twenty years of age will glass six hundred 
" splits" per day. 

The " splits" are next " pasted" with a preparation of flour 
paste placed on the top of the blacking on the grain side. 

They are then hung up in the finishing-room and allowed to 
dry over night, and in the morning are reglassed, and are then 
immediately finished by gumming them over with gum traga- 
canth dissolved to about the consistency of jelly. Sometimes a 
preparation of fish oil and rosin is applied, which application 
depends upon the softness of the leather after being gummed. 

The " splits" are then assorted for different weights, and are 
measured and rolled up, ready for market. 

Finishing Grain Leather. 

The "grains" having been blacked, as has been described, 
are hung up in the finishing-room and dried, after which, if the 

Fig. 233. 




side is to be "pebbled," it is carried to the "jack" and pebbled 
on the grain side, after which it is grained on the grain side 
with an armboard shown in Fig. 243. The sides are next pol- 



516 THE MANUFACTURE OF LEATHER. 

ished on the same side bj means of a revolving wheel ; the 
pattern shown in Fig. 233 being largely used for this purpose. 

After being polished, the sides are again grained with the 
arm board, and immediately oiled with a mixture offish oil and 
paraffine, and then measured for market. In graining " pebbles," 
the sides are " cut" four ways, the same as for Morocco leather. 

The " straight grains" are finished in the same manner as the 
"pebbles," except that a different roller is used in the "jacking 
machine," and in graining they are "cut" only from one 
direction. 

Finishing Buffed Leather. 

After the leather has been scoured either by hand or machin- 
ery, it is then hung on poles in the open air to harden, after 
which it is "set out" on the grain side with a stone so as to 
make it solid^ and free it from the grain, and it is then stuffed. 
This variety of leather is often stuffed by hand, and it is per- 
formed by laying the side of leather on a table, flesh side up, as 
shown in Fig. 137, and working over it with a steel slicker, after 
which a preparation of fish oil and tallow is applied with a brush 
to the flesh side. The sides are then hung up in the loft to dry, 
being placed on sticks in tiers, and in this manner they remain 
suspended usually for about three days. 

The superfluous grease is then removed from the flesh side 
by means of a slicker ; but sometimes this operation is per- 
formed by a machine, which is called by the curriers a " grease 
jack," and is shown in Fig. 164. 

The leather is now in condition for buffing, which, when done 
by hand, is performed by placing the side on a slanting table 
covered with leather, and removing the grain by means of a 
whitening or buffing slicker, which is shown in Fig. 165. One 
man will buff from fifty to seventy sides of leather per day, the 
number varying with the condition of the leather and the skill 
of the workman. The machines used for whitening and buffing 
leather are shown in Chapter XXIII. In order to improve the 
appearance of the edges, the sides after being buffed are next 
trimmed around with a common shoe knife. 

They are then placed on a flat table, fifty sides being piled 



GRAIN SPLIT AND BUFFED LEATHERS. 517 

one on top of another with the grain up, and the batcli is then 
blackened with a composition of logwood and water boiled 
together, which is rubbed into the leather with an ordinary 
blacking brush, samples of which are shown in Figs. 18-t and 
185, or the sides may be blackened by machinery. 

After the pack has been thus treated the sides are then 
blackened with another compound of irou rust and copperas. 

The sides are then replaced upon the table, flesh to flesh, and 
are, then "smutted," which operation is performed usually by 
working over the blacking with a woollen cloth in order to 
remove dirt and sediment, and improve the appearance of the 
blacking. 

Bryant's machine for " smutting" leather is shown in Figs. 
196 and 197. 

The leather is next glassed in order to make it " fine" and 
remove all the creases, and. when the glassing is done by hand 
the side is placed on a table and the blacked portion worked 
over with a glass slicker. The sides are then hung up in the 
finishing-room for a short time, and then "pasted," which is 
an application of flour paste over the blacking, and commonly 
put on by means of a sponge. After being thoroughly dried, 
the sides are "soft-boarded" by working them with the flesh 
side up, and one man will soften about one hundred sides per 
day. 

The leather is then laid upon a table and slicked off clean on 
the flesh side, and then immediately glassed on the grain side, 
after which it is gummed with a preparation of gum traga- 
canth made of about the consistency of jelly, and applied over 
the paste. 

The sides, after being hung up and dried, are then assorted, 
measured, marked, and bundled, and the buffed leather is then 
ready for market. 



618 THE MANUFACTURE OF LEATHER. 



CHAPTEE XXXI. 

GERMAN HARNESS LEATHER — VACHE-LEATHER — MACHINE 
BELT LEATHER GREASED WITH TALLOW. 

Green hides, if possible, are used for these varieties. As 
many hides as can be placed in the lime pit are, after cutting 
out the horns, soaked in running water six to eight hours with 
frequent rinsing, next cleansed from dung and placed in weak 
milk of lime for twenty-four hours. They are then taken out 
and replaced, after preparing fresh lime, for twenty -four hours 
more, when they are again handled. After this they are regu- 
larly handled. Depilation is eftected as soon as the hair can be 
easily pulled out, after which the hides are soaked in water for 
a few hours. Water-stripes and dots are produced by soaking 
the hides too long in running water, and allowing them to re- 
main stationary. After fleshing and soaking for twenty-four 
hours the hides are smoothed and placed in the bate for one to 
three days, according to their thickness and the state of the 
weather. They are handled three times everyday they remain 
in the bate. If the England wheel shown in Fig. 112 is em- 
ployed the bating can be accomplished in from eight to ten 
hours. Special attention should be paid to this process, as soft 
leather can only be produced by proper bating, while too much 
bating is injurious, as it destroys the skin fibres and the grain. 
After taking the hides from the bate and rinsing in fresh water 
they are again smoothed, and after soaking for several hours 
thoroughly worked upon the flesh side with a dull fleshing 
knife. They are then ready for tanning. 

Salted hides of cows and oxen are soaked three days, special 
attention being paid to remove all the salt before placing the 
hides in the lime pit. Dried hides after thorough soaking and 
bringing them back to their original shape by stretching, are 



GEEMAjS" haeness leathee. 519 

treated in the same manner as green hides. By using the hide 
mill described in Chapter XIV,, much labor in stretching and 
smoothing may be saved, and for inferior hides, slicking also. 

The handling vats should be sufficiently large to allow of the 
convenient handling of the hides. 

It is generally preferred to place the leather in old liquor for 
one or two days, according to the quality of the liquor in the 
vat. The leathers are taken out and replaced and treated in 
the same manner as above, after ladling out the old tan and 
adding one third bushel of fresh tan. According to the state of 
the weather the power of the tan will be exhausted in four to 
eight days, it then becoming necessary to freshen the vats. 
After doing this twice or three times more the leathers are 
placed in the lay-aways, where they remain for about the same 
period as for sole leather, a longer period being as a general 
rule only required for stout harness and vache-leatlier, but it is 
absolutely necessary for belt leather. 

In order to see how far tanning has proceeded it is advisable 
to split the leathers after the second layer. The cut of a thor- 
oughly tanned hide will be uniformly brown, while a pale yel- 
low or white coloring is a proof of insufficient tanning. 

After splitting the hides into sides and numbering the two 
halves with the same number, the completely tanned leather is 
rinsed in old ooze and smoothed with a dull fleshing knife upon 
the beam. Where all three kinds of leather are made, the best 
hides are used for harness leather, the strongest for belt leather, 
and the poorest for vache-leather. 

The harness leather is gone over with a fine-edged knife and 
then greased upon the flesh side with a mixture of linseed oil 
and tallow, and hung up to dry. Yache-leather is also greased 
but only slightly upon the grain side and then dried. 

Preparation of Y ache- Leather . 

The dried hides are soaked in sufficient well-water to cover 
them in a vat, handled after an hour, then replaced and allowed 
to soak over night. The next day they are placed upon a 
wooden table, and after tucking in the hoofs rolled up grain side 



520 THE MANUFACTURE OF LEATHER. 

in from the head to the tail, so that every half hide forms a roll. 
The rolls are tied together with strong twine or leather straps 
so that they will not become unrolled in the succeeding beating 
with fluted wooden mallets, which is continued until the hide 
feels soft to the touch. 

To soften them completely they are boarded, after beating, 
upon the grain side with a coarse graining board. After work- 
ing ten or twelve hides in this manner a thin shaving is taken 
from the flesh side. The best plan is to have two workmen 
perform the above operations and also the succeeding ones. In 
tanneries provided with a fulling mill a higher degree of sup- 
pleness can be imparted to vache-hides by fulling than is possi- 
ble by beating and boarding with the graining board. 

One-half of the hide is then placed upon a somewhat inclined 
table of wood, slate, or zinc, as shown in Fig. 137, as long as the 
hide and as wide as one-half the hide, and scrubbed with brushes 
constantly dipped in water until the flesh side acquires a mushy 
condition, which can be recognized by the impressions made by 
passing the fingers over the hide remaining visible. It is then 
turned over and, after placing the back part in a straight line 
with the edge of the table and passing the hand over the hide so 
that it sticks to the table, the grain side is treated in the same 
manner. 

The slicker is then driven first along the back to prevent the 
wrinkles which are formed from sticking, and then in the direc- 
tion from the back to the fore-hoof. After removing the 
wrinkles, which is absolutely necessary, more force may be 
used for the removal of tan depressions. 

As soon as one half of the hide is slickered it is immediately 
hung up in the drying loft. If this is higher than the length 
ot the hide, the latter is nailed through the hind hoof and root 
of the tail to short strong sticks, or incisions are made in these 
places, and after passing through the sticks the latter are placed 
between two poles. 

If the loft is not very high, the back part of the hide is nailed 
to straight strong poles, which after tying the front and hind 
hoofs with twine in such a manner that they cannot hang down 
and form wrinkles, are placed in the pole-rack. 



GERMAN HARNESS LEATHER. 521 

After the hides are partly dry, they are phiced separately 
upon the table and, after wetting slightly such parts as have 
become too dry, one hide is placed above the other and the pile 
repacked. The hides moistened first are then replaced upon 
the table and after fitting the back exactly to the edge of the 
table it is fastened with a few wooden clamps, the impressions 
of which are removed later on. 

To remove all tan depressions and to give the leather a beau- 
tiful appearance and firm touch, the use of a roller is of great 
advantage, especially as it facilitates the currying and prevents 
the grain from being injured hy constant working. 

The tan impressions, etc., are then entirely removed, and after 
rubbing with a moist woollen rag the sides are stamped and 
hung up. 

Before the hides become entirely dry the halves are fitted 
together according to the numbers and placed grain side upon 
grain side and hide upon hide until a pile is formed, which is 
covered with planks somewhat loaded. 

After remaining here for twelve hours they are hung across 
poles and gradually dried. Each hide is then rolled up sepa- 
rately and about six placed in one bundle, which is secured with 
twine. 

It is scarcely necessary for us to say that scrupulous cleanliness 
must prevail during all these operations. By strictly following 
the directions given, an article fulfilling all demands will be the 
result, and one which is not only equal to the best Frankfurt 
vache-leather, but in most cases surpasses it as regards beauty 
and quality. 

After the harness leather has passed through all the above 
operations it is sorted into brown and black. The first acquires 
lustre by means of a glassing machine, or is sold without it. 
The black leather after grounding with decoction of logwood is 
blacked with iron black and, when nearly dry, passed through 
the press. 

The best qualities of light hides from Buenos Ayres, Monte- 
video, and Texas may also be used for vache-leather. The lime 
used for hides intended for vache-leather and inside sole leather 
is sometimes mixed with red arsenic. This has a better ef!'ect 



522 THE MANUFACTURE OF LEATHER. 

upon the hide, also softening hard places found in these hides 
which are always dif&cult to soften. In using this mixture the 
hides require more frequent handling than in the ordinary 
liming process, and should be depilated as soon as possible. As 
the hides are not raised by the mixture it may also be recom- 
mended to subject them to the ordinary liming for a day after 
taking them from the arsenic and lime liquor. This method of 
liming can also be advantageously employed in preparing green 
hides and kips for upper leather, but the after-liming must ,be 
continued for a correspondingly longer time. 

Machine Belt Leather greased with Tallow. 

By greasing with tallow this leather acquires the desirable 
property of not becoming hard even if the belt cut from it has 
to pass, as is frequently the case, through water. This leather is 
tanned in the same manner as has been described for sole leather, 
complete tanning being the principal requisite. 

After dividing the hides into sides and rinsing off the tan, 
the sides are scoured either by hand or machinery so as to pre- 
pare them for the reception of the tallow. The sides are then 
treated differently from the leather that is to be used for uppers 
of boots and shoes, in that it is not dampened and tempered, as 
has been described for heavy upper leather. Bat the sides 
after being scoured are dried in heat ; in summer by spread- 
ing them out and exposing them to the direct rays of the 
sun, and in winter in a room having a temperature of at least 
110° F. 

Pure tallow, best ox tallow, is melted in the meanwhile in a 
portable boiler, a temperature of 167° F. being the best for the 
purpose. This temperature should be kept up after the tallow 
is melted, which can be effected by keeping the boiler over a 
small coal-fire or, still better, by placing it in another boiler 
with hot water, which is kept hot over a fire while the work is 
going on. 

One of the heated sides is then placed upon the table and 
the fluid tallow applied with a brush. The hide sliould be so 
thoroughly saturated with the tallow as to be entirely permeated 
with it, and the tallow applied to the flesh side become visible 



GERMAN HARNESS LEATHER. 523 

upon the grain side. Should the tallow congeal upon the sur- 
face before permeating, it is allowed to soak in by placing the 
hide in the sun or near a warm stove, but if the hide is already 
thoroughly permeated, the excess of tallow must be removed. 

Currying the Tallowed Leather. 

The sides having lost their good appearance and become dark 
by greasing with tallow, are soaked in water for twenty-four 
hours and then placed upon the beam, and the tallow still adher- 
ing to the flesh side removed with a blunt knife. After placing 
them again in water, each side is taken out separately, and after 
spreading it upon the table and covering with a layer of spent 
tan one-half inch thick, it is rolled up, and the roll, after secur- 
ing it with twine, beaten with a mallet, until the leather has 
again acquired a light color and its original suppleness. 

After rinsing off the tan the hides are again beaten, with 
frequent dipping in water in case they should feel too dry. 
They are next smoothed in the same manner as for the ordinary 
machine belt leather. 

It is recommended to have two men to do the work, it being 
too fatiguing for one. 

The manufacture of this variety of leather, though very 
laborious, repays doubly the work expended upon it, principally 
by the increased weight the leather acquires by the absorption 
of tallow. 



52-i THE MANUFACTURE OF LEATHER. 



CHAPTEE XXXII. 

MOROCCO LEATHERS. 

Section I. Tanning- and Finishing Imitation of French 
Kid, Brushed Kid, Straight Grained Gtoat, Pebbled 
Goat, and Oiled Goat. 

By Morocco leather we understand that soft, pliable material 
so largely employed in the manufacture of the uppers of ladies' 
and children's shoes, and gentlemen's low cut shoes, and which 
also finds various secondary employments, such as bindings for 
books, linings for travelling bags, toilet cases, pocket books, etc. 

The finer grades of Morocco leather are produced from goat- 
skins, but an inferior quality is obtained from sheepskins, and 
split calf-skins. 

The usual commercial classification of Morocco leather, pro- 
duced in this country, is : — 

Imitation of French kid. Pebbles. 

Brushed kid. Straight-grained goat. ' 

Oiled goat. Caracal, or straight calf. 

Pony-glazed kid. Siamang. 

Glazed kid. 

The goat-skins employed in this country for the manufacture 
of Morocco leather, are classed as follows, and rank according 
to their position in the list : — 

Curacoa. Russians. 

South Americans. Capes. 

Madras. Arabians. 

Tampico. Macedonians, 

Patnas. Angoras. 

Mochas. Albanians. 

Kassan. Magadores. 




be 



= H 






MOROCCO LEATHERS. 525 

Glove-calf and glove-sheep are also sub-names for Morocco 
leather, and are used principally for toppings for button, laced, 
and congress boots for ladies' and gentlemen's wear. Sometimes 
shoes for elderly gentlemen and ladies have the uppers made 
entirely of these leathers, which are desirable for this purpose, 
being soft and comfortable to the feet. 

When glove-calf and glove sheep are kept dry they continue 
soft, but when frequently wetted the tannin is drawn from the 
leather, which renders it hard and liable to crack. 

A large portion of the skins used in this country for the 
manufacture of glove-calf and glove-sheep ^re produced in the 
CJnited States; but South America and Russia also send us large 
quantities. The imitation French kid made in this country 
will remain pliable under continued wetting much longer than 
the genuine French kid. 

The tanning material usually employed for all the stock which 
has been mentioned is sumach, which is used in the proportion 
of about one-half Sicily or imported, and one-half Virginia or 
native. 

The process of preparing the skins for the reception of the 
tannin is about the same for all the stock that has been named. 

Preparing the Shins. 

When the dry skins are removed from the bales, they are 
placed in the " soaks," which are vats containing clear cold 
water, and remain for from three to five days, the period of 
course depending upon the condition of the skins, the hardest 
requiring a longer soaking than those that are softer. 

From the " soaks" the skins are removed either with hooks 
or tongs, and placed, usually 150 to 200 at one time, in the "pin- 
mill," which softening contrivance has been described on page 
250, and when sufficiently softened the skins are next placed in 
the " limes." 

Fig. 234 shows a view of the lime-vats, in a Morocco tannery, 
and over one of the pits is shown a pile of skins which have 
been removed therefrom and placed upon planks to drain, while 
in the background is shown the " wash wheel." Above each 
lime-vat there is a small blackboard upon which are marked in 



526 



THE MANUFACTURE OF LEATHER. 



chalk the number and kind of skins in each vat and the date on 
which thej were put in. 

In large Morocco tanneries usually 1350 South American 
goat-skins are limed at the same time, and about 600 glove- 
calf, and 800 glove-sheep are placed in separate vats at once. 

The goatskins remain in the " limes" about 14 days, glove- 
calf 12 days, and glove-sheep 8 days. 

They then go to the unhairing beams and are unhaired by 
hand, and one man will " unhair, flesh, and slick" about eigb-ty 
skins per day. 

Fig. 235. 




After being unhaired the skins are placed in a mill and 
thoroughly washed to free them from adhering lime, and are 



MOROCCO LEATHERS. 527 

next placed in the slightly heated bate of dog or pigeon manure, 
in which they remain over night. 

Upon removal from the bate the skins are " slated," which is 
the removal of the fine hair remaining upon the skins after the 
unhairing operation. The "slater" is a tool closely resembling 
a " slicker ;" but the edge of the " slater" is ground sharp. 

The skins are now passed into the bran drench, which is com- 
posed of bran and water, slightly heated, and in this they remain 
over night, and are then in condition to be sewed together. 

The sewing is usually performed on heavy chain stitch 
sewing machines, operated by women, who are paid at the 
rate of about ten cents per dozen skins. 

The usual form of machine employed is represented in Fig. 
235, and it is made to sew either way, being one thus adapted 
to all classes of sewers ; it is strong, and thoroughly fitted for 
the hard and dirty work to which it is subjected, and may be 
run by foot or steam power. 

The skins are sewed in the form of a bag, the only opening 
left being one at the end of the hind shanks, which is to allow 
the spigots on the sides of the tan-tubs to enter and thus force 
the tannin into the interior of the bag. 

Tanning. 

The skins are sewed grain side out, and when placed in the 
tannin liquor the shanks are placed over the spigots, the skins 
tied to them with twine, and the liquor forced into the skins 
with a gentle pressure by means of a pump. 

The vats are filled with sumach liquor in which the skins are 
submerged, and three hours is usually sufficient time to complete 
the tanning. When it is desired to hasten the tanning process, 
the pressure from the pump is increased. 

Fig. 236 shows a view of the tan-tubs in a Morocco factory, 
and Figs. 287 and 238 show the manner in which the skins are 
attached to the spigots and a method by which the skin-baos 
are filled with the sumach liquor. 

The invention shown in Figs. 237 and 228 is that of John Gr. 
Baker, of Wilmington, Del., and it consists of a vat or tank with 
a feeding-pipe leading into a horizontal pipe at one end of the 



528 



THE MANUFACTURE OF LEATHER. 



tan-tub, connecting at each end with another pipe or tube pro- 
vided with cocks or spigots, set at regular intervals, to the noz- 



Fiff. 237. 




zles of which, facing the centre of the tan-tubs, are fastened 
by tying, the skin-bags to be tanned, so that the liquor will flow 



Fis. 238. 




into and suspend them in the liquor contained in the tub while 
under a pressure in combination with the tan-tub and its stand- 
pipe. 



MOKOCCO LEATHEES. 529 

By this invention it is sought to provide an improved mode 
of filling and pressing sheep and goat skins while being tanned 
without their coming in contact with the sides or bottom of the 
tub or with each other. 

It is a well-known fact that if the skin-bags press against 
each other or against the tub, they will be but imperfectly 
tanned, and also that where skins are suspended by their necks 
in a vertical position their weight when distended causes them 
to break or tear away from the nozzle. 

In Figs. 237 and 238, A is the tan-tub ; B is the tube attached 
to the walls of the tub, and connecting with the feed-pipe ; G is 
the feed or supply-pipe for filling the bags from the vat or tank ; 
I) is the vat or tank ; E is one of the cocks of the tub, to the 
nozzle of which the skins are fastened ; and G is the stand-pipe 
or overflow-pipe to keep the liquor at a uniform height. 

The reservoir, feed-pipe, and tubes with their cocks are not a 
new idea, as they are described in the invention of Dr. Alexander 
Turnbull, of England, who obtained a patent in this country 
September 26, 1844, and also in the patent issued to Dudley and 
Brooks of Portland, Me., dated October 23, 1834, But the dif- 
ferences between both of the plans which have been named and 
the present one are plainly obvious, as the skins in both of those 
patents come in contact with each other, or with the floor or 
walls of the tan-tub. 

In Turnbull's plan the skins are laid upon the floor of the vat 
and partly submerged, and require turning, and in the other 
patent the skins are suspended by their necks, and are but partly 
submerged, and so hung as to come in contact with each other, 
while in the present instance they are so arranged and hung to 
the tubes or pipes, as to render contact almost impossible, and 
are buoyed up by the liquor. Warner's apparatus for tanning 
goat and sheep skins is shown in Figs, 244 to 249, and G, C. 
Walters's filling cup in Figs, 250 to 253, and Halsey's combined 
vat and wheel in Figs. 255 and 256. 

The skins are taken from the tan-tubs and when full of liquor 
are piled one upon the other in open vats provided for the pur- 
pose at each end of the tanning-tubs, and thus the liquor is 
34 



530 THE MANUFACTUKE OF LEATHER. 

gradually pressed oat and passes into a receiver, from whence it 
is pumped back into the tanning vats. 

After the liquor has been squeezed out, the bags are removed 
from the open vats and one end of the thread cut with an 
ordinary shoe knife, thus allowing the thread to be pulled out 
at one operation. 

The skins next go into the England wheel vat, which has 
been shown in Fig. 112, and are "wheeled" in sumach liquor of 
about 20° strength, which is the same as in the tanning vats. 

Striking Out and Drying. 

The skins are next "struck out" on mahogany tables, which 
are so shaped as to slant from the workman at an angle of 
about 45°. 

A steel " slicker" is used for this operation, and an average 
workman will " strike out" about 200 skins in ten hours. 

The object of this operation is to increase the size of the 
skins, remove the adhering " fleshings," tanning liquors, and 
water, and render the skins smooth and even, and this is accom- 
plished in some tanneries by the employment of machinery, 
shown in Pigs. 257 to 261. 

The skins after being "struck out" are hung up in the drying 
lofts and dried by the atmosphere ; the time required for this 
depending upon the condition of the weather. 

Fig. 239 shows the drying loft in a Morocco factory, the 
skins being hung on hooks which are shown on the racks placed 
at a convenient height from the floor. When sufficiently dry 
the skins are removed from the hooks and carried to a room on 
the same floor as the loft, and there assorted according to the kind 
of leather into which they are to be finished. This important 
point having been decided upon, the skins are removed to the 
cellar and wetted down in soap-water, and while wet the skins 
are carried to a currier's beam and shaved with a currier's knife 
on the flesh side, so as to make them of a uniform thickness, and 
also for the purpose of having them receive a better finish. 

From this point all the skins pass to the finishing-room, and 
as each kind of Morocco leather requires a different treatment. 



►^ 
(n 



^ ■ 




MOROCCO LEATHEES. 531 

we will now describe each separate mode of finishing the various 
kinds. 

Finishing Imitation of French Kid. 

This class of leather has taken a high rank in our countiy, 
and it is now generally conceded to be much superior to the 
genuine French kid for wear. 

The skins, after being treated as above described, are carried 
to the coloring table and colored on the grain side, with an iron 
and nutgall-black having a logwood body which gives a clear 
and bright black, and after being blacked the skins are hung 
up in the loft. The skins, after the first blacking has dried, 
next pass into the finishing-room, and the second application of 
black is made, which is similar to the first, with the exception 
of the nutgalls, which are omitted ; bichromate of potash is some- 
times used in this black, but in small quantities. After this 
second application of color, the skins are hung upon racks in 
the finishing-room, and left until the color sets or dries, the 
blackened side being turned inward, as shown in Fig. 240, 
which shows a perspective view of the blacking tables and an 
interior perspective view of the finishing room. 

After being removed from the hooks they are next moistened 
with a solution of milk and water, and are then ready to be 
glazed, which operation is performed by machines of various 
constructions, and which have been heretofore explained in 
Chapter XXYI. Knox's machine, shown in Fig. 211, is much 
used for glazing this variety of Morocco. 

The skins are next softened by hand with a board and 
scraper, or, as it is termed, a " softening slicker." 

They are then oiled with the best sperm oil, which is applied 
with a rolled-up flannel cloth. 

The skins are glazed two or three times as the case requires, 
the oil is applied twice, and after the last application the imita- 
tion French kid is ready for market. 

In selecting skins for the production of this class of leather, 
their weight is regulated by the demands of the trade, at times 
being light, and at others heavy. The skins are also selected 
for their cutting qualities, those which are free from blemishes 



532 THE MANUFACTURE OF LEATHER. 

or breaks being, of course, more valuable than those that are 
scratched. 

Finishing Brushed Kid. 

The finishers take the South American goat- skins from the 
shaving-beams and " put them out," and each man will put out 
and black five dozen per day, and after being thus treated they 
are hung in the loft and dried by the atmosphere. 

The skins are blacked and seasoned with the same prepara- 
tion of bullock's blood, iron, and vinegar black which is applied 
with a piece of flannel cloth made into a roll. They are then 
wet over with gum-water and brushed with a very soft brush, 
called a "kid-brush." After being hung ia the loft and dried, 
the skins are next "back-boarded," then glassed, and next rolled 
by a machine having a steel roller. The Knox machine shown 
in Fig. 211 is commonly used for glassing and rolling. 

The finisher takes the skins from the rolling machine and 
scrapes them with a steel slicker in order to loosen up the flesh, 
after which the grain side is oiled with the best sperm oil, 
which is applied by means of a roll of flannel cloth. The 
brushed kid is now completed and ready for market. 

Finishing Straight- Grained Goat. 

The first step after shaving in finishing this variety of 
Morocco is the " putting- out," which is performed by working 
over both sides of the skin with a steel slicker. This portion 
of the work is sometimes accomplished by machinery, such as 
is shown in Figs. 257 to 261. When done by hand about five 
dozen large skins or nine dozen small ones are put out by a 
skillful workman in one day. The skins thus treated in the 
morning are placed in the loft, and in the afternoon they are 
" put out the second way," which consists in smoothing the 
grain side. They are drawn oui and the stretch removed in 
the first operation. 

When the skins are placed in the loft they are spread out 
separately on the floor, as shown in Fig. 2-41, and are not allowed 
to become too dry, and in the afternoon when they are " set out 
the second time," no water issues from them. After being set 



MOROCCO LEATHERS. 533 

out the second time thej are returned to the loft and placed on 
trestles, which are about two feet six inches high, and they re- 
main in this loft until dry, the period of course depending upon 
the state of the weather. 

The day's work of each man is kept separate from that of 
the others, and each workman hangs up his own day's work of 
skins, one on each hook, and so placed that none of them touch 
each other. 

When dry the skins are packed in piles, those that are in- 
tended to be stained on the flesh side being separated from those 
that are to be pebbled. 

They are next carried to the finishing-room and the rough 
part of the grained side is smoothed off with a piece of fine 
emery paper, rolled so as to expose the length of the paper to 
the skin. 

This portion of the work is sometimes accomplished by 
machinery; a revolving emery stone, such as is used in the 
manufacture of kid gloves, being employed, the dust being blown 
from the stone by a suitable fan. 

The skins are next seasoned, which is accomplished by coating 
them with a preparation of bullock's blood, logwood boiled, 
cow's milk, water, and a small quantity of vinegar black, made 
by treating iron with vinegar, one gill of the latter preparation 
being used for a bucketful of " seasoning," which quantity 
will season above five dozen straight-grained goat-skins. After 
the seasoning has dried they are regularly blacked and hung up 
in the finishing- room, as shown in Fig. 240, and after remaining 
on the hooks for about one and one-half hours, or until the 
dampness leaves the skins, they are rolled by machinery ; the 
machine shown in Fig. 211 being largely used for this purpose. 
After being rolled the skins are again hung up in the finishing- 
room and remain over night, and in the morning they are glazed 
on a machine having a glass roller, the one shown in Figs. 204 
and 209 being much used for this purpose. 

The number of skins rolled or glazed is from 30 to 50 dozen 
per day for each machine, depending upon the speed at which 
the machine is driven and also upon the size of the skins and 
quality of the work. Some are glazed lighter than others, in 



584 



THE MANUFACTURE OF LEATHER. 



order to give a medium gloss, but when a high gloss is desired, 
extra pressure is applied. Fig. 242 shows a perspective view of 
the portion of the finishing-room in which the skins are being 
rolled and glazed. 

After the skins are glazed they are wetted in cold water by 
passing them through a large tub holding about 50 gallons, and 
the workman in accomplishing this takes two of them and 
places them grain to grain, and grasping hold of the butt of the 
skins draws them slowly towards him. 

They are next grained, which may be performed either by 
hand or machinery ; if done by hand, a graining board similar 
to that shown in Fig. 242 is employed. 

Fig. 243. 




These graining boards are made with a cork face, and in 
using them the arm passes through the strap and the hands 
grasp the handle. 

The object in using this tool is to raise the grain and to make 
the straight-grained goat-skins more durable, and also has the 
effect of rendering them more pliable as well as tougher. 

The skins are again hung in the loft usually above the 
finishing-room and dried by the atmosphere, which requires 
from 24 to 48 hours, according to the state of the weather. 
After this drying they are again grained, which has the tendency 
to raise the figure and further mellowing them. All the graining 
is done on the grain side ; but after the second graining they are 
" back-boarded" on the flesh side, which has a tendency to make 
the figure more uniform as well as to still further soften the 
skins. 

An application of best sperm oil to the grain side of the skins 



w 



oq 

S 



iTi 




MOROCCO LEATHERS. 535 

completes the finishing of straight-grained goat, and as the oil 
is immediately absorbed by the pores, the skins are at once 
ready for market. 

From the time that they enter the finishing shop to the time 
that the straight-grained goat is ready for market, the period is 
about seven to ten days, being shortest in good drying weather 
and longest when the condition of the atmosphere is not favor- 
able. There is also a grade of Morocco leather known as " cara- 
cal," which is straight-grained calf, and its peculiarities are 
pliability, toughness, gloss, and superior finish. This leather has 
a fancy finish, and its introduction into the trade has been but 
to a limited extent. 

Finishing Pehhle- Grain Goat. 

The difference in finishing pebble-grain goat from that of 
straight-grained is that the first named is "cut" four ways in 
the process of hand-finishing, in the softening, and in the " spring- 
ing up ;" but in " back-boarding" it is cut two ways only. The 
skins are pebbled on the same machine, but not with the same 
roller that is used for straight graining. 

Finishing Oil Goat. 

In finishing " oil goat," after the skins have been " put out 
the second way" and blacked, they are then stuffed with dubbing 
on the flesh side. The dubbing is composed of one-half oil and 
one-half tallow when used during the winter time ; but in the 
summer more tallow than oil is used. They are then hung up 
to dry, after which they are grained three ways and then treated 
to a coat of dubbing on the grain side, after which they are 
flattened down on the grain side with a dull slicker, and after 
being treated with a coat of fine sperm oil which completes the 
finishing, the oil goat-skins are then measured and marked 
ready for the trade. 

This class of Morocco leather is more water-proof than the 
other grades, and is used for ladies' heavy wear, and sometimes 
boys' boots are made from it. 

The heaviest skins are used for this kind of leather, and the 
kinds commonly employed are Tampico, Capes, and Patnas, 



536 



THE MANUFACTURE OF LEATHER. 



Section II. Tanning Apparatuses for Goat and 
Sheep-Skins. 

Warnerh Aj^jjayntus. 

The apparatus shown in Figs. 244: to 249 for tanning goat 
and sheep-skins is known as Warner's Apparatus, and was 
invented in 1870 by William Y. Warner and James Crooks, of 
Wilmington, Del., and the fittings for it may be obtained from 
G. W. Baker, Wilmington, Del. 

Fig. 244. 




The first part consists in the combination of a feeding-trough 
for containing tanning-liquor, filling-hose with funnel-connec- 
tions, and valved ends, a gauge-box with slides for feeding tan- 
ning-materials into the skins or hides, operated by means of a rod 
and spring, having attached to it a tapering pipe, which receives 
the tanuing-material in its passage into the skins, and a smaller 
pipe, which leads the water from the liquor-feeding trough into 
this tapering pipe. 



MOKOCCO LEATHERS. 



537 



The object is to obviate tlie necessity of using a funnel and 
dipper in- the filling of the skins with tanning-material and 



Yisr. 245, 




Fig. 246. 




538 



THE MA^SrUFACTURE OF LEATHER. 



liquor, and to enable the workman to fill both at the same time, 
without waste. ' 

The second part consists of a valve, which is applied to the 
month or opening of the skin which retains the liquor, when 
distended or filled. 

The object of this is to dispense with the troublesome pro- 
cess of tying and untying the mouths or necks of the skins, in 
filling, and, at the same time, retaining the tanning-material. 



Fiff. 247. 



Fia-. 248. 





Fig. 249. 




Figure 244 is a front view of a machine embodying Warner 
and Crooks's invention ; Fig. 245 an end view ; Fig. 246 a longi- 
tudinal section ; Fig. 247, a section of the valve in the hose ; 
Fig. 248, a vertical transverse section, showing the end of the 
machine, which is at the right hand in Fig. 244 ; and Fig. 249 
is a section through the centre of the gauge-box and its slides. 



MOROCCO LEATHERS. 539 

A is tlie feeding-trough, wliicli is attached to the joists of the 
floor above the workman's head. 

B is the filling-hose, with funnel-head Cand valve D attached. 

-E' is the gauge-box with its slides S S, operated by means of 
the rod X and spring Y, for regulating the quantity of tanning- 
material used. 

F is the tapering pipe, through which the material passes into 
the skins. 

G is the pipe which carries the tanning-liquor from the 
feeding-trough A into the tapering pipe F, for the purpose of 
forcins; the tannino;:-material into the skins or hides. 

H is the valve, which is fastened to the mouth of each skin 
or hide. 

/is the bin for holding the sumach, or tanning-material. 

^is the tan-tab, in which the skins are filled, and from which 
the liquor is pumped back into the feeding trough A, when re- 
quired. 

The skins to be tanned, after sewing, have the valve IT at- 
tached. The liquor is pumped from the tan-tub K into the 
trough A, which runs the whole length of the tan-tub. 

The sumach, or other tanning-material, is fed from the bin / 
through the gauge-box F. 

In filling, the skins or hides are taken to the tapering pipe F, 
the end of which is inserted in the mouth or neck of the skin, 
forcing open the valve H. The slides S S, in the gauge-box jE', 
are pulled forward, the tanning-material descends, the valves 
S S closing instantly, while the liquor which is constantly run- 
ning through the small pipe G, washes all into the skin, which 
is then removed, and passed to the workman stationed in charge 
of the filling-hose i?, who brings the mouth of the skin under 
the valved end of the hose, which forces up the valve D^ and 
the skin is entirely filled. Here, the operation is complete, and 
the skins or hides remain in the tan-tub until it becomes neces- 
sary to refill them. 

Walters' s Filling- Cup for Morocco Manufacturers. 

The filling-cup for Morocco manufacturers shown in Figs. 
250 to 253 was invented in 1881 by George C. Walters of 



540 THE MANUFACTURE OF LEATHER. 

Philadelpliia, Pa,, and the invention consists in the novel con- 
struction and arrangement of a valved cup having a valve-seat 
above the valve, an outwardly projecting extension, to which 
an extension on the rubber or other flexible valve is secured by 
screws driven outwardly from below at angles of about seventy 
degrees to the plane of the valve, and an encircling flange at 
the bottom of the cup, whereby the leg of the skin may be 
securely attached to the cup. The skins are first sewed in the 
ordinary manner at the edges, as has already been described, 
and the valved cup applied to an opening in the end of one of 
the legs of the skin by tying the cup therein. 

The old form of valve consisted of a circular cup with an 
outward projection in its inner edge or opening, around which 
the skin was tied. The valve rested on the outer surface of 
the inner edge of the cup and extended to the extreme edge. 
This construction permitted the valve to be dragged open when 
it came in contact with anything while handling the filled skins, 
and permitted the liquor to escape, which accident resulted in 
only partially tanning the skins. In the old form the projection 
to which the valve was attached was on the inner side of the 
cup. This construction lessened the opening in the cup, caused 
clogging, and produced an overflow of the filling material, 
which could only be replaced by guess-work. The screws were 
also passed through the valve at right angles to its horizontal 
plane, whereby it did not bear with suf&cient force on the edge 
of the cup when the skins were partially emptied, and from that 
cause the liquor would escape. 

By Walters's construction it is claimed that these objections 
are removed, as, in the first place, the valve is seated within the 
cup and cannot be displaced by accident in handling the filled 
skins; and, secondly, the projections on the cup and the valve 
in connection with the inclined screws, hold the valve more 
firmly, and the interior periphery of the cup is not obstructed, 
and is therefore not liable to clog, either during the filling or 
the emptying of the skin. A funnel is inserted into the cup 
and secured during the filling operation, and the sumach is 
placed therein, and a stream or drip of water from above falls 
thereon and produces a tanning-mixture of about the consistency 



MOEOCCO LEATHERS. 



541 



of cream. After filling, the funnel is withdrawn and the valve 
closed. The skins may then be piled for storage. 

Figure 250 is a representation of a perspective view of 
Walters's device. Fig. 251 is a bottom view. Fig. 252 is a 
sectional view, and Fig. 253 is a vertical section as applied. 



FiV. 250. 



Fig. 251. 





Fis. 252. 



FiR. 253. 





A designates the cup, of metal or other suitable material, 
having the valve-seat B at its lower edge, as shown. iV desig- 
nates a flanged projection entirely surrounding the cup, whereby 
the skin may be securely attached to the cup, and G the out- 
wardly-projecting extension, having the outwardly-inclined 
threaded holes a a for the reception of the screws Z>, which 
secure the valve D in place in its seat. The valve D is prefer- 
ably of rubber, and has an extension, ^, corresponding in shape 
to the extension C, to which it is secured by screws /), washers 
c being interposed between the valve and the screw-heads. 



Hayid Method of Tanning Morocco. 

In many of the small Morocco tanneries the skin bags are 
tilled with sumach liquor, as shown in Fig. 254, and after being 
inflated with the breath are tied with strings and made to float 



542 THE MANUFACTURE OF LEATHER. 

in sumacTi Jiquor by constantly agitating them so as to facilitate 
the action of the tanning material. 

Fi?. 254. 




The process is repeated until the skins are tanned, when the 
bags are removed from the tub and piled upon one another and 
left to press and drain. After this the skins are unstitched and 
rinsed, then scraped lightly on the beam and hung in the drying 
loft. 

Tanning Morocco in a Combined Wheel and Vat. 

The apparatus shown in Figs. 255 and 256 was invented in 
1883 by D. Halsey, Jr., of Newark, N. J. 

In the use of sumach in tanning goat-skins and Morocco, as has 
been explained in this chapter, the skins are commonly sewed up 
and the liquor and ground sumach placed inside of them, and are 
then placed in contact with the same substances in a tan-vat. By 
the use of this wheel the sumach is kept suspended in the liquor 
in the desired manner, and the skins are turned over and over in 
contact therewith, so as to produce satisfactory results, both in 
regard to the time consumed and the quality of the work per- 
formed. The sumach, however, settles to the bottom of the vat 
when the motion of the wheel ceases, and to remove it con- 
veniently the vat is constructed above ground and provided 
with the door J/, shown in Fig. 255, at the bottom for the con- 
venient removal and rinsing out of the sediment. Fig. 255 is a 
transverse section of this wheel and vat on the line x x in Fig. 
256, the latter being a plan. 



MOKOCCO LEATHERS. 



543 



A is the vat; B the wheel; C a gear of ring form secured 
to the periphery of the wheel at one edge ; I) a door for the 



Fig. 255, 







Fig. 256. 




M-K 



insertion and removal of the hides from the wheel ; IE a pinion 
for driving the wheel, and F a shaft mounted in bearings G 
above the wheel, and provided with a pulley, H^ to receive a 
driving-belt, /. 



544 THE MANUFACTURE OF LEATHER. 

The wheel is mounted by gudgeons e/in bearings K^ which 
are secured upon posts fastened to the sides of the vat at a suita- 
ble distance to make the bottom of the wheel clear the floor of 
the vat. 

L L are cleats fastened to the inside of the wheel's rim to 
move the hides, and J/ is a door in the side of the vat, near the 
bottom. 

iVis a clutch provided upon the shaft, in connection with the 
pinion E^ to stop and start the wheel at pleasure. The clutch 
would be moved by a handle, as is usual, and enables the opera- 
tor to disconnect any one of several tumbling-wheels, if more 
than one be driven by the shaft F. 

is a fastening for one end of the door D^ the other end 
being held in place by inserting it under the iron ring-gear C. 

P P are holes formed in the sides of the wheel for the free 
circulation of the tanning-liquor, so that the contents of the 
wheel will not be retained in contact with the same fluid con- 
tinuously ; but an automatic exchange of the fluids in the wheel 
and the tank will be effected by the movement of the wheel. 

The operation of the apparatus is as follows : About six feet 
in diameter- is considered a convenient size for the wheel, and 
the skins are placed in the wheel and rotated in the tan-liquor 
about three to six revolutions per minute by the application of 
suitable power to the shaft F. The skins, when stirred by the 
movement of the wheel, tend to float more or less in the liquor, 
and are constantly moved about in a current created by the 
movement of the Avheel. The liquor outside the wheel is raised 
a little by its contact Avith the periphery of the latter at one 
side, and correspondingly depressed at the opposite side, where 
the wheel's rim is descending, thus producing a change of level 
in the liquor at the front and rear of the tank. The liquor in- 
side the wheel is similarly affected, and thus tends to flow from 
the apertures P at one part of the wheel and into the apertures 
at another part, thus securing the circulation desired. When 
the operation is continued a suitable length of time, the door is 
opened and the skins are removed. 

The tan-liquor may be removed from the vat either before or 
after the removal of the skins, as preferred, and fresh liquor 



MOEOCCO LEATHEES. 545 

may be furnished to tbe vat, without stopping the wheel, by 
drawing off a portion of the spent liquor at a time and supply- 
ing an equal amount of fresh. 

Section" III. Putting-out Machines for Morocco. 

The work of '' putting out" goat and sheep-skins in the pro- 
cess of manufacturing Morocco leather is commonly done by 
hand ; but during the past few years machines have been in- 
vented for this purpose that are steadily coming into use. 

The skin is "put out" after being taken out of the tanning- 
vat, and previous to being hung up to dry. The object is to 
press out the water and tanning liquor, and to scrape off the 
small pieces of flesh or other imperfections that adhere to the 
flesh side of the skin, and to render the grain side smooth and 
otherwise to improve its appearance. 

Mg. 257 shows a perspective view of Vaughn's machine for 
"putting out" skins, and it also claims to do other work, such 
as unhairing, fleshing, scouring, and "setting out" hides and 
skins. This machine is patented in all the principal countries. 
The machine is very efficient, and it leaves the skins dry, even 
smooth, and in a most desirable condition. 

Necks, butts, and shanks are also put out by it in a better 
manner than it is possible to perform the work by hand. The 
measurement of nearly all skins put out by this machine is 
increased fully live per cent, over hand work. 

Hoffman's Putting-out Machine is shown in detail in Figs. 258 
to 261. It is a cheaper machine than the one shown in Fig. 
257, and it may be used for goat, sheep, or calf-skins. 

Figure 258 is a back view of Hoffman's machine. Fig. 259 a 
side elevation, showing a portion of one of the pulleys broken 
away, so as to expose the pinion and spur-wheel on the other 
side of it. Fig. 260 is a cross-section through the machine, and 
Fig. 261 is a front elevation of the machine complete. 

The frame a of the machine is constructed of wood ; a' is the 

putting-out cylinder, provided with the spiral blades a^. The 

cylinder a' is usually made of wood, and the spiral blades are of 

thin strips of brass rigidly secured thereto. They are arranged, 

35 



546 



THE MANUFACTUKE OF LEATHER. 



as shown, to meet near the centre of the cylinder, so that the 
spirals on each side rim in opposite directions. The object of 



Fiff. 257. 




this is to cause the skins to be stretched each way during the 
operation of the machine. This cylinder is provided with jour- 
nals a^ a\ arranged in boxes made in any well-known way. The 
driving-pulley a^ (see Fig. 259) is connected directly to the 
journal or shaft a*, and consequently with the cylinder. 



MOKOCCO LEATHERS. 



5i7 



a^ represents a small pulley rigidly secured to the journal or 
shaft a^. This pulley is connected by a belt, Z>, to a larger 



Fig. 258. 




pulley, v. On the shaft of the pulley S' is secured a. smaller 
pulley, h^^ from which a belt, If^ passes to the pulley ¥. On the 



548 



THE MANUFACTUEE OF LEATHER. 



inside of the pulley ¥ is a pinion, />°, which gears into a spur- 
wheel, W, which is connected to the shaft c of the wooden roller 
c'. (See Fig. 260.) 



Fiff. 260. 




Fig. 261. 




MOROCCO LEATHEES. 549 

The object of the belts is to give a much slower motion to 
the roller c' than the motion of the cylinder a\ the motion of 
the cylinder being about three hundred and fifty revolutions, 
and the motion of the roller c' about twenty-five. On the 
inside of the frame is a pinion, c^, near either one or both sides 
of the frame. It is connected to the shaft of the roller c', and 
turns with it. 

(? represents a roller made of some yielding material — India- 
rubber for instance. This roller is mounted in boxes in the 
slotted arms c*, which are connected to the arms c^ by means of 
a bolt and nut, the bolt passing through the slots ,c° into the arms 
c^, so that the roller may be thereby rigidly secured to the arms 
and be capable of an adj ustment to or from them. The arms & are 
rigidly fastened to the shaft c?, which shaft is mounted in boxes 
d' . The boxes d' are set in place (see Figs. 259 and 260) so as 
to be capable of a movement up or down, and are kept down 
by a spiral or other spring, d^. The roller c' is made of a hard 
wood, and is secured in boxes in the frame. (See Figs. 259 and 
260.) 

d^ represents a slotted arm secured to the arm e® by means of 
a bolt, a^, which passes through the slot d^. It will be seen 
that this arm is made adjustable. Its object is to secure the 
adjustment of the roller c^ to or from the putting-out cylinder, 
after which it is rigidly secured in place by the bolt d'^. There 
are two arms, c' — one at each side of the machine. At the outer 
ends of the arms is jointed by a pin, e, in the usual way, a con- 
necting-rod, e' — -one on each arm. The opposite ends of these 
connecting-rods are secured in a similar way by pins ^ to the 
arms e^ of the foot-step e^ The arms ^ are connected to a shaft 
e^ A counter-weight, /, on the shaft e' causes the foot-step to 
rise after the pressure of the foot is taken off of it. 

In operating the machine the skin is thrown over the roller 
& and the rollers started slightly by hand, until the skin is far 
enough in to be caught between the rollers & and c' . A pressure 
on the foot-step then brings the two rollers together, and still 
greater pressure brings the roller c^ and the skin against the 
cylinder by lifting the box d' up against the spring d^ ; this 
cylinder revolves rapidly and cleans off the small pieces of 



550 THE MANUFACTUEE OF LEATHER. 

fiesli or other matter adhering to the skin. It also takes out 
the wrinkles or other imperfections, and stretches the skin both 
ways, as above mentioned, so as to leave it smooth and clear. 
This operation finishes one-half of the skin. It is then taken 
out and the opposite end treated in the same way, thereby com- 
pleting it. By this arrangement the skin is first gripped firmly 
between the rollers c' c^, which hold it and cause it to move 
with the required speed. By increasing the pressure slightly 
on the foot-step the roller c^ is brought toward the putting-out 
cylinder, and the skin is brought in contact with it, and is slowly 
carried past it, moving in a direction contrary to the movement 
of the putting-out cylinder. One advantage in thus being able 
to first bring the rollers c' & together is that it enables the 
operator to wring out the water from the skin, if at any time 
necessary, before bringing the skin in contact with the putting- 
out cylinder, which is often necessary on account of holes in the 
skin. It will also be noticed that as the rollers c' c^are brought 
together the wheels c^ g are brought into gear, and as the roller 
g' is continually turning it thereby imparts its movements to 
the roller c^ until released from it. The skin being put over 
the roller c^ is always in sight, and thereby enables the operator 
to let off the pressure of the skin from the putting-out cylinder 
when coming to a hole or a spot on the skin that may be tearing. 

List of all Patents for Putting-Out Machines, issued hy the Government 
of the United States of America, from 1790 to 1883 inclusive. 

No. Date. Inventor. Residence. 

274,858) Mar. 27, 1883. J.W.Vaughn, Peabody, Mass. 

274,859) 

288,941 Nov. 20, 1883. W. M. Hoffman, 

Leather Flirffing and Grounding Machines. 

No. Date. Inventor. Residence. 

235,249 Dec. 7, 1880. J. M. Jones, Wrexham, N. Wales, 

Great Britain. 



MOEOCCO LEATHERS. 551 

List of all Patents for Machines for Evening or Making Leather of 
Uniform Thickness, issued hy the Government of the United States 
of America, from 1790 to 1883 inclusive. 



No. 


Date. 




Inventor. 


Residence. 


69,219 


Sept. 24, 


1867. 


W. C. Joslin, 


West Thompson, Conn, 


147,770 


Feb. 24, 


1874. 


C. Handy and 
C. E. Morrill, 




152,811 


July 7, 


1874. 


J. Pu.llman and 
J. R. Edmonds, 


Wonercli, England. 


270,964 


Jan. 23, 


1883. 


J. D. McDonald, 


Woburn, Mass. 



Section IV. Compounds for producing Imitation of 
Grain or Morocco Leather. 

This invention, wliich is that of Mr. Hugh Smith, Newark, 
N. J., consists in producing from split or buffed leather an 
imitation of grain leather or Morocco, made from any kind of 
skins or hides, by the use of certain compounds ; the first 
consists of glue, one-quarter to one pound, dissolved in one 
gallon of water, and boiled, after which is added thereto one- 
quarter to one pound of starch or flour, and the whole mixture 
is again allowed to boil, after which aniline colors or paints of 
any kind may be added ; also, use from one to four pounds of 
glycerine or other fatty substance, and mix therewith any 
desired colors of paints to correspond with the colors of the 
dyes. The whole is mixed together. Of this compound one 
or more coats may be used previous to graining or pebbling the 
leather under treatment, the object of which is to fill up the 
pores, and bind down the fibre or nap on the surface ; and if it 
is not required to be water-proof, it may be finished with one or 
more coats of a suitable varnish. 

The second compound, which is used to make the leather 
more flexible and water-proof, consists in a syrupy solution 
'of the following ingredients, and in about the following pro- 
portions: One pound of gum-shellac dissolved in two quarts 
of alcohol, added thereto or used separately ; one pound of 
India-rubber or other equivalent gum, also dissolved in one 
gallon of naphtha (the latter should be dissolved in a separate 
vessel previous to mixing with the former), and adding thereto 



552 THE MANUFACTUEE OF LEATHER. 

a sufficient quantity of glycerine to soften, together with the 
proper or desired coloring matter. If this mixture should be 
too thick, it may be reduced by adding wood-alcohol or its 
chemical equivalent until the desired result is obtained. 

These compounds are to be applied to the leather in the known 
manner, and for the purpose of coverings or coatings thereto. 

The leather is first split or buffed in the ordinary manner, 
and dyed, if preferred, any desirable color. It is then secured 
to frames, or spread or sticked out upon a table, preparatory to 
having the coloring matter and compound applied, which is 
done with a sponge, brush, swab, or any other suitable device, 
and well rubbed in upon the surface of the split or buffed side 
of the leather, one or more coats, either warm or cold, being 
applied, until a uniform color and smooth surface are produced, 
which, after being properly dried, is grained, to imitate the 
natural grain of the leather or Morocco or other design, as the 
case maybe, the first preparatory coating to be applied previous 
to the graining or pebbling process. 

Process for Finishing Lower Grades of Leather similar to 

Morocco. 

In preparing leather for market, metallic salts have been used, 
and with other chemical compounds and dyes been made to 
combine with the substance of the leather for the purpose of 
rendering the material impervious to moisture, and thus to 
strengthen the fibre and give it a suitable color and finish for 
the various manufacturing purposes. The fibre of leather not 
being readily absorbent of compounds containing metallic salts, 
the beneficial effect of the treatment has been confined to skins 
or leather of the higher grades of quality only. The material 
has been found not to retain permanently the metallic salts or 
color of the dye, and is liable to exude. The metallic salts and 
coloring-matter thus injure the appearance of the leather, caus- 
ing the color to fade and the leather to crack, thus rendering 
the usual methods objectionable on account of the higher grade 
of skins it is applicable to and the want of permanence in finish. 

The object of the present method is to provide a process for 
finishing leather which will render the fibre of the leather of 



MOROCCO LEATHERS. 553 

all grades more absorbent of the chemical compounds and dyes, 
and will also set and retain the color and the metallic bases of 
the compounds used, and give a durable finish to leather of all 
grades, and make the lowest grades susceptible of a finish equal 
to Morocco leather. 

The process consists in the previous use of a certain prepara- 
tory solution and dyeing compounds, in combination with a 
secondary and a perfecting compound applied and used in the 
manner and order and composed of the ingredients as will be 
described, one essential requisite of this process being that the 
treatment shall be followed strictly in the order here designated. 

For the first part of this process, after the leather has been 
tanned and shaved in the ordinary way, saturate with a liquid 
compound composed of a hot solution of logwood made by boil- 
ing ten pounds of logwood-chips in forty-five gallons of water 
until reduced to twenty-five gallons, which is designated the 
"preparatory solution." Second, the leather is then put on 
tables for stretching and taking the water out, then hung up 
and partially dried. Third, sammy it, then put out on the 
tables the second time. Fourth, if it is Morocco and required to 
be straight-grained or pebbled, do so by the use of an arm-board 
or machinery. Fifth, it is then blackened by the use of a liquid 
compound composed of a solution of iron, vinegar, and animal- 
blood, either warm or coagulated, made by suspending eight 
pounds of iron in forty gallons of vinegar, thirty grains test, 
for three weeks; and to one quart of this solution add half a 
pint of animal-blood, either warm or coagulated, and this appli- 
cation is sometimes repeated ; then hang up the skins and allow 
them to dry ; or the leather may be blackened by dyeing in 
trays, by saturating with a liquid compound composed as follows: 
Say copperas, one pound ; nitrate of iron, one pound; verdigris, 
one-half pound ; chromate of potash, two ounces ; Sicily sumach, 
two pounds ; soda-ash, one-fourth pound ; pulverized nut-galls, 
two pounds ; water, forty gallons. To color leather bufi' and 
grain it, add to this last solution four ounces of animal-blood to 
the quart, and put it on with brush or sponge on the table. 
Sixth, if a bright finish is desired, glaze with the glazing- 
machine or on the table with a glass or flint. If a dull finish 



554 THE MANUFACTURE OF LEATHER. 

is desired do not glaze, but brush on the face with a brush. 
Seventh, soften on the table by use of board or slicker. Eighth, 
oil the face of the leather, after which the process is continued 
as follows : — 

For the second part of this process use a chemical compound 
which consists of, say one part of dry gelatine (isinglass or 
other like substance) dissolved in four parts of oil, including a 
small quantity of sulphuric or other acid, and when these are 
combined by means of heat, five parts, or thereabout, of an alka- 
line solution of caustic soda are added at a specific gravitj^ of 
about 26° Baume, the whole being stirred while yet warm, and 
the result is a chemical combination which is designated the 
" secondary compound." 

For the third part of the process iise a chemical compound 
which is designated the " perfecting compound," and which is 
prepared as follows: In one vessel is prepared a strong solution 
of one of the alums — for instance, of the sulphate of alumina — 
with potassa or either ammonia or soda as equivalent. In 
another vessel is prepared a solution of the sulphate of zinc, 
and in a third vessel a solution of the acetate of lead. These 
solutions are each to be of the same density. When prepared 
the two sulphate solutions are mixed in the proportions of about 
five parts of the first to one and a half parts of the latter, and to 
these are added about five and a half parts of the acetate-of-lead 
solution. By the chemical action that ensues sulphate of lead 
is formed, and when this has subsided the clear liquid is drawn 
off and is reduced to the proper density, which is 1° to 2° 
Baume. 

The manner of continuing the treatment of leather to be 
finished is as follows : A bath is prepared with, say half an 
ounce of the secondary compound dissolved in two gallons of 
hot water — that is, in about these proportions. This is used 
when cold. To treat leather the patentees, Moses B. Tice and 
Nicholas O'Connell, steep it in this bath till endued with its 
properties and then drain it. When the leather has been re- 
moved from the bath of the secondary compound and is well 
drained, they steep it in a bath of the perfecting compound, 
where it remains from eight to twelve hours, and when well 



TANNING AND FINISHING SHEEP-SKINS. 555 

drained it is gradually dried, wliicli completes the "finishing 
process. After the finishing process is thus complete the 
leather is again softened by use of board or slicker, then oiled 
to bring the color out and make it soft and pliable, and properly 
prepared and ready for manufacturing purposes. This finishing 
process gives to leather of all grades a satin finish which is very 
durable. 

The preparatory solution, by being first applied, and then the 
liquid compounds for coloring being afterward applied, fasten 
the color at once, and there is not required so much of coloring- 
matter as heretofore used, which is beneficial to the leather, for 
the reason that the less coloring-matter used the stronger is the 
leather, and by thus coloring before using the other finishing 
compound, which has not heretofore been done, the color is 
fastened, and will not fade or come out. 



CHAPTER XXXIII. 

TANNING AND FINISHING SHEEP-SKINS. 

Section I. Tanning and Finishing Sheep-Skin Fleshers 
FOE Linings, Binders, and Skivers. 

The manufacture of sheep-skins into linings, bindings, and 
skivers, for use in the production of boots and shoes of all 
grades, is an important one. In this country the majority of 
the sheep-skins used for this purpose are consumed in the State 
of Massachusetts, the large production of boots and shoes at 
Lynn and other places in that State creating the demand for this 
class of leather. 

The sheep-skins used are both domestic and foreign ; those 
derived from Great Britain are mostly " sheep-skin fleshers," 
and are treated with vitriol before shipment to preserve them. 



556 THE MANUFACTURE OF LEATHER. 

The materials used for tanning this variety of leather are 
usually hemlock bark, sumach, and alum. 

These skins are finished in all colors ; hemlock is used for 
colors darker than its own, sumach is employed for white and 
fancy colors, and alum mostly for those that are to be dyed 
black. 

The compounds and machines employed for depilating and 
pulling wool from sheep-skins have been explained in Chapters 
XY. and XVI., and machines for splitting them are shown in 
Chapter XX. 

The sheep-skin fleshers are split from the sheep-skins while 
in a state of pelt, and special machines are required for this 
operation. 

The processes which we shall first describe are for those 
skins which arrive at the tannery from foreign countries, split, 
free from wool and which are green salted. 

Sometimes these skins are placed in clean water and washed ; 
but they are not uncommonly removed from the casks in which 
they were shipped and immediately soaked and placed in the 
tanning liquor, whether it be hemlock, sumach, or alum. 

In hemlock and sumach they remain about ten or twelve 
days, the strength of these liquors being gradually increased 
every thirty-six hours, and in alum the skins remain for a much 
shorter time. After being tanned, they are removed from the 
vats with a hook and piled, and left to drain, as shown in Fig. 263. 

The skins are then carried to the drying lofts and each one 
hung upon two hooks, but so placed that the skins do not touch. 

Fig. 264 shows an interior view of a drying loft in a sheep- 
skin tannery, with the skins hanging upon hooks to dry. 

Fig. 262 shows an exterior perspective view of a sheep-skin 
tannery, and the slat openings into the drying lofts for the free 
admission of air. 

After being dried the skins are removed from the hooks in 
the drying loft, and transferred to the "putting out depart- 
ment," where they are wetted and tacked to boards used for 
putting out. After this operation they are again hung up in 
the loft to dry, and then carried to the "finishing-room" and 
finished on the machines employed for that purpose, but if they 



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•5d 






3? = 










« =1 



0<? = 











^ <a 



be 



TANNING AND FINISHING SHEEP-SKINS. 557 

are to be dyed, they are carried to the dye-house and colored in 
various hues, aniline colors being generally employed. Differ- 
ent receipts for dyeing sumach-tanned skivers and the dyeing of 
alum tanned and other varieties of leather are enlarged upon in 
Chapter XLIII. The reader is, therefore, referred to that por- 
tion of this volume for information upon the dyeing processes. 

After being dyed the skins are again hung up in the lofts to 
dry, and are next carried to the finishing department, shown in 
Fig. 265, and rolled, glassed, or pebbled by machines used for 
the purpose, and which have been illustrated and explained in 
detail in Chapter XXYI. 

After being finished on the machines, the skins are measured, 
marked, and bundled ready for market. 

Dressing Sheep-Sldn Fleshers for Glove Bindings^ etc. 

The following process for dressing "sheep-skin fleshers," to 
be used in the manufacture of gloves, for hidings, etc., 'was 
patented in 1875, by Eichard Hart, of Gloversville, N. Y. ' 

The quantity of the mixtures to be specified is intended for 
about two dozen sheep-skin fleshers of the ordinary size. In 
carrying out the process, first immerse, pound, and stir the skins 
for about one-half hour in a fluid mixture, prepared as follows: 
Dissolve one pound of alum in one and a half gallons of water, 
which is readily done by boiling. Then mix, in a separate 
vessel, one-half pound each of flour and oatmea], or one pound 
of either alone, with one gill of oil and one and a half gallons of 
water, and mix this composition with the alum-water. At the 
expiration of the designated time take the skins out of this mix- 
ture and stretch them, and remove the groundwork and knife- 
marks from the grain side. Then immerse them for about the 
same length of time, and with the same manipulations as before, 
in a fluid mixture, prepared as follows : One gill of urine, one- 
half bar of bar-soap, one-half ounce of soda, one-half pound of 
salt, and about two ounces of whiting or ochre, all boiled in one 
and a half gallons of water until they are thoroughly dissolved, 
to which are added one-half pound of flour and one-half pound 
of oatmeal, or one pound of either alone, mixed in one and a 
half gallons of cold water. The skins are then dried, stretched, 



558 THE MANUFACTURE OF LEATHER. 

and staked out, and can now be faced or finished upon either 
side in the usual manner. 

Instead of urine in the mixture last described, a small quantity 
of ammonia may be used, as it produces the same eft'ect ; or the 
proportion of soda may be suitably increased, and neither urine 
nor ammonia be employed, and still the desired result obtained. 

Skins dressed by the usual method can be finished or faced 
on the flesh side only, and have a rough and hard surface on the 
grain side, besides being rough and stiff in texture. 

Skins dressed by this process, by treatment to both mixtures, 
may be finished on either or both sides, and, it is claimed, are 
made soft, pliable, and with elasticity or "spread," and stronger 
in texture, without becoming rough. 

Skins which are treated to the first mixture only may be at 
once dried, staked, and stretched, and finished on either or both 
sides in the usual manner, without subjecting them to the 
second mixture, and, it is claimed, will then be better in quality, 
and have a susceptibility of better finish, than skins dressed in 
the ordinary way ; but it is preferable to employ the entire process 
in dressing skins, as they are thus given a superior quality and 
a capacity for higher finish than when the first part of the pro- 
cess only is used, and, when finished, bear a close resemblance, 
in texture and quality, to deer-skin or castor. 

Section II. Improved Methods for Tawing and Dressing 

Sheep-Skins. 

Manasse's Method for Taiving Sheep-Skins. 

In 1875 Emanuel Manasse, of ISTapa, California, patented the 
following process for tawing sheep-skins : — 

The skins are taken from the sweat-house, and, after being 
properly treated in the beam -house, are immersed in a solution 
composed for two hundred skins of the following ingredients : — 

No. 1. Twenty pounds of salt, thirty pounds of white-rock 
potash, three hundred gallons of water. 

The skins remain in this solution for about two hours, and 
are then wrung out dry, and immersed in a solution composed 
as follows : — 



TANNING AND FINISHING SHEEP-SKINS. 559 

No. 2, Twelve pounds of hard soap and two gallons of neat's 
foot oil in one hundred and fifty gallons of water. 

After being kept in this solution long enough to wet them 
through, the skins are removed and hung up to dry, and are 
wet and dried in this manner two or three times. 

After being thus treated and properly tawed, they are put 
in a dry state into clear water, and washed in a thorough manner 
to remove all foreign matter from them, and in this moist con- 
dition are dried to produce leather of various colors, or, if a 
white leather is required, they are allowed to dry without fur- 
ther treating. 

The proportions of the ingredients given above may be 
changed, as the nature of the skins requires, without affecting 
the process. 

It is claimed that the skins thus treated combine the qualities 
of softness, pliability, and toughness, which allow the leather to 
be sewed together, as in the manufacture of gloves and like 
articles, without tearing or allowing the stitches to pull out. 

Hibhard's Process for Pre'paring and Tanning Sheejj-Skins. 

Hibbard's process for preparing and tanning sheep-skins for 
linings, binders, etc., is as follows : — 

To remove the hair mix the following composition with water 
suf6cient to make a thick paste, apply it to the flesh side of the 
hides, fold the skins and keep them at a temperature of summer 
heat. In a few hours they are ready to pull. 



Quicklime (freshly slacked) . . .J bushel. 
Wood ashes . . . . . • 2 " 
Salt ........ 3 pints. 



For the liming process use the same composition, mixed with 
sufficient water in a vat to immerse the number of skins pro- 
posed to be limed. One bushel is equivalent to one bushel of 
lime alone. The liming is done at the temperature of 60° F. 

For tanning six dozen full sized sheep, deer, goat, or similar 
skins, prepare the following composition : — 



560 THE MANUFACTUEE OF LEATHER. 



Salt . . . 


. 18 lbs. 


Sulphuric acid 


; 2 " . 


Sumach or quercitron bark . 


. 36 " 


Hydrochloric acid 


2 ounces 


Dried clover .... 


. 18 lbs. 


Water 


. 125 galls. 



Exbaust the sumach or bark by water, add the salt, enough 
to insure perfect solution, then add the acids and incorporate 
by stirring. 

HesthaVs Process for Dressing Sheep- Shins ^ etc. 

The following process was patented in 1883 by August 
Hesthal, of San Francisco, Cal., and is useful in the preparation 
of leather for button-pieces, linings, stays, and other small 
articles. 

The process is especially applicable to sheep, lamb, kid, and 
deer-skins. The skins after having passed through the sweating 
process and been properly treated in the beam-house are placed 
in a solution which we will call No. 1, composed of two pounds 
of caustic soda, one pound of borax, and sufficient water to cover 
the skins — say one hundred gallons. 

The skins and compound are contained in a suitable drum, in 
which they are run for a half hour and then removed and hung 
up to dry. 

They are then immersed in a solution which we will call 
solution No. 2, composed of five pounds of hard soap, one gallon 
of straits oil, one-half pound caustic soda, and seventy-five 
gallons of water. 

In this solution they remain long enough to become soft and 
wet through, after which they are put into a drum with a part 
of the composition No. 2 and run for about a half hour, being- 
then removed and dried as before. 

They are next softened in the composition No. 2 and then 
allowed to drip. 

They are then placed again in the drum with a solution 
which we will call No. 3, and run for about a half hour ; then 
put back into the composition No. 2 and soaked for one hour, 



TANKING . AND FINISHING SHEEP-SKINS, 561 

and then taken out and hung up to dry, after which they are 
soaked and dried in this manner two or three times in composi- 
tion No. 2 until they are properly prepared, as some skins may 
need to have this part of the process repeated a greater number 
of times than others. After the skins are treated in this manner 
and have become leather, they are put in a very weak solution 
of composition No. 2, in order to thoroughly soften them, and in 
this wet condition they are dyed in different colors ; or, if white 
leather is required, they are allowed to dry without further 
treating. In this manner is produced a leather which is strong 
and pliable, and when sewed together it does not crack, nor do 
the stitches pull out ; and as the skins are prepared without the 
employment of lime and sulphuric acid, it leaves the fibres in 
their natural state and strength. 

The proportions of the ingredients given in the above solu- 
tions, Nos. 1, 2, and 3, are estimated for about one hundred and 
twenty sheep-skins. 

Section III. Artificial Sheep-Skins for Linings. 

Artificial leather does not properly come under the head of 
tanning ; but in a book that treats of the whole subject of 
leather manufacture as broadly as does the present volume, it 
would probably be more out of place to omit such subjects than 
to include them. Especially is this so when such materials are 
in common use in this country and in Europe, and are employed 
in the manufacture of cheap boots and shoes. 

Evans's imitation sheep-skins are prepared as follows : — 

Having selected a base of closely-woven cotton cloth or other 
fabric, of ordinary width and of any desired length, spread upon 
it in successive layers a composition of caoutchouc or India- 
rubber, and shellac, gasoline or naphtha, zinc-white, clay, or 
plaster-of- Paris, of sufiicient thickness and body not to spread 
or run too easily. 

Each layer is thoroughly dried before the next coating is 

applied ; and better results are obtained by making the coats 

thin and applying them oftener — say as many as six or seven 

successive applications of the composition — for the reasons that 

36 



562 THE MANUFACTURE OF LEATHER. 

a thin coating is more evenly spread on the fabric than a thick 
one, and dries more quickly and more uniformly, so that as many 
as six or seven thin coatings can be applied to the fabric, and 
each one be thoroughly dried before the next following is 
spread, in the time that it would take for spreading one thick 
coating and in drying the same ; and the result of the thin- 
layer process is far superior to the thick-coating method, as the 
first layer is thoroughly incorporated or knit into the fabric 
before the others are applied, and each successive lay.er is 
thoroughly and firmly attached to each preceding layer. 

After the last coating is wholly dry apply a surfacing of any 
one of the aniline colors, somewhat stiffened by the addition of 
French chalk or magnesia, which after being thoroughly mixed, 
is spread upon the base as prepared, in much the same way as 
the first-named composition is applied, excepting that but one 
coating of the preparation is put on. 

After this last-named coloring-coat is dry, the fabric is passed 
through a pebbling-machine, to provide it with a surface-finish 
that shall more closely resemble the pebbled sheep-skins used 
for the linings of boots and shoes. 

The product of this series of manipulations, it is claimed, pos- 
sesses a softness of finish that renders its detection from sheep- 
skin by the touch alone almost impossible, while its strength 
and wearing qualities are good, and its cost is materially less. 

In preparing the composition first applied, cut the caoutchouc 
or India-rubber with gasoline or naphtha ; then add to that mix- 
ture a proper quantity of shellac, zinc-white, cla}^, and plaster- 
of-Paris, about in the proportion of one part shellac, two parts 
zinc-white, one part clay, one part plaster-of-Paris. These 
ingredients are thoroughly incorporated with each other before 
use. Of course the proportion of the parts may be changed if 
desirable. Enough French chalk or magnesia is employed to 
somewhat thicken the aniline. 

In the manufacture of this article the patentee takes about 
three hundred yards of the fibrous base and winds it on a feed- 
roller, from which it is fed under a reservoir containing a 
quantity of the first-named preparation, which is dripped there- 
from on the fabric immediately in front of a spreading-knife 




LACE LEATHER. 563 

for equally distributing the coating on the cloth. From the 
spreading-knife the cloth, having one coating, is carried over a 
drying-roller under another reservoir, from which is sprinkled 
the composition which is spread bj a second spreading-knife 
over the first coating. The cloth now having two coats of the 
filling composition, is drawn over another drying-roller from 
which it passes back to a roller immediately under the feed- 
roller, to be again drawn through the machine to receive addi- 
tional coatings. 

Although other filling having an alumina base may be em- 
ployed in place of the zinc-white, clay, and plaster-of- Paris, yet 
the best results are secured by their use. 



CHAPTEK XXXIY. 

LACE LEATHER. 

Lace leathers are either tanned, tawed, or made from raw 
hides, and both these varieties as well as picker leathers which 
are used for looms, and also for hamestrings, are generally pro- 
duced in the same tannery. But the variety of lace leather 
which we shall describe in this chapter is the lighter kind, which 
is manufactured usually from Calcutta hides, the heavier variety 
being made from light cow-hides. 

When the dry Calcutta hides are used they are first placed 
to soak in a vat of water, and the time whicli they remain is 
dependent upon the weather, one or two nights in warm 
weather and three or four nights in cold weather being the usual 
time. 

They are next softened in the hide-mill, the time which they 
are worked depending upon the manner in which the hides 
have been cured. 

In order to cleanse them from dirt the hides are next placed 



564 THE MANUFACTURE OF LEATHER. 

in the wasli-niill and worked for fifteen or twenty minutes, which 
operation also removes the wrinkles. 

Upon being removed from the wash-mill, the hides are spread 
flat upon the floor and slit down the back and thus divided into 
sides. 

They are then placed upon trucks and carried to the lime- 
vats, where they are spread flat upon the floor alongside the 
vats and whitewashed, by passing over them a swab which has 
been dipped in a solution of lime. 

This coat of whitewash is applied to the hair side, and the 
sides are piled two hundred high, and in warm weather this 
pack remains over night, but in winter the sides are placed in 
the lime-vats the same day, in order to prevent the whitewash 
from chilling. In warm weather the sides remain in the limes 
about ten days, but in cold Aveather the period is longer. 

When the hair is loosened the sides are removed from the 
vats with tongs and immediately unhaired, after which they are 
placed in water in a vat having a revolving paddle wheel and 
washed, the England wheel and vat shown in Fig. 112 being 
the one commonly employed and upon removal are worked on 
the beam to remove the lime. 

As a further preventive against lime the sides are placed in 
a large revolving wheel, called a "tub wheel," in which they 
are washed for about three-quarters of an hour, and upon removal 
from this wheel the sides are placed in the tanning liquors and re- 
main until tanned. When this has been accomplished the sides 
are exposed to the air to dry and next stretched, a machine for 
which purpose is shown in Figs. 266 to 268; but the stretch- 
ing is also performed by hand on the stretch-bench. 

As is well known, all hides vary considerably in thickness at 
diflerent points, and when taken from the liquor- vats they are 
found to be soft, flabby, wrinkled, and fulled. Owing, therefore, 
to this condition of the hides, it is necessary, before they are 
dressed and finished for the market, that they be stretched 
throughout to remove the wrinkles and fulness, and also to re- 
duce those parts which are thicker than other portions, so that, 
as far as possible, the hides shall be uniform in thickness. 



LACE LEATHER. - 565 

Mechanical devices are capable of producing, in connection 
with hand manipulation, the desirable results of thoroughly 
stretching the hides, and rendering them of even ..thickness in 
all parts. These devices usually comprise, in the main, a friction 
table or beam, over which the hides are dragged, a stretcher-bar 
of suitable form for stretching the hides transversely, and a 
slowly-revolving roller, to which the edge of each hide is 
secured, and around which it is wound after being drawn over 
the table or beam and the stretcher-bar. After the sides have 
been well worked on the stretch-bench they are split evenly by 
the splitting machine. 

The sides are next stuffed with tallow and neat's-foot oil, the 
proportions of which change somewhat according to the tem- 
perature and season, less oil and more tallow being used in 
summer than in winter. 

The sides are then hung upon sticks in tiers in the drying- 
room, which is commonly heated by exhaust steam from the 
engine. 

After being removed from the drying-room the sides are 
softened, the machine shown in Figs, 269 to 277 being now 
usually employed for this purpose in place of the old-fashioned 
pin-block. 

The sides are next rolled out smoothly on a glassing machine, 
and are next shaved on the flesh side and buffed with a currier's 
knife, in which latter operation the grain is removed in order to 
prevent the lacing from cracking ; about seventy-five sides being 
a fair day's work for one man. They are then rubbed with a 
mixture of lard oil, tallow, and flour, and the sides of lace- 
leather are then finished by laying them upon a flat table and 
smoothing them out with a glass slicker. 

Junior's Methods of Manufacturing Lace-Leather. 

The following process for manufacturing lace-leather is used 
by Junior of Belleville, 111., There is no patent on the process,, 
but Mr. Junior claims one on the tanning compound. 

The hides in this method go through the following pro- 
cesses : — 

First. Soak the hides in fresh water for twenty-four hours. 



566 • THE MANUFACTURE OF LEATHER. 

Second. Soak the hides in freshly slaked lime-water as long 
as necessary to make the hair removable by scraping. 

Third. Put the unhaired hides into fresh lime-water once 
more for two days. 

Fourth. Scrape off all fleshy parts on the inside ; then soak 
the hides in fresh water to free them from all lime. 

Fifth. Then rub the hides with a " slick-stone," in order to 
smooth or burnish them and to squeeze out all impurities. 

Sixth, Soak the hides for about twelve hours in warm water, 
containing one pound of wheat bran and one-half pound of a 
ferment to every five gallons of water, until the hides cease to 
swell, and all lime is neutralized. 

Seventh. Then squeeze them well with the scrape-iron. 

Eighth. Immerse the hides in the composition given below, 
in which they remain for from twelve to twenty-four hours 
until they are well saturated. 

This composition consists of the following ingredients com- 
bined in proportions stated : For every ten pounds of hide — 
pure water, five gallons ; alum, one pound ; sal-soda, four 
ounces ; common salt, four ounces ; wheat bran (or other bran), 
four ounces. Of these ingredients the crystalline salts should 
be thoroughly dissolved and mingled by agitation with the bran. 
It is claimed that the application in tanning of this solution, 
in connection with the other treatment of the hides has the 
efiect of preserving the whole natural strength of the same, 
which is possible only in the absence of free acids. After the 
hides have become saturated, they are removed from the solu- 
tion and hung up to dry. 

Ninth. Now work them well on the stretch-bench and split 
them evenly on the splitting-machine. 

Tenth. Eub into the hides a mixture of about three pounds 
of lard oil and one pound of tallow, and let dry well. 

Eleventh. Soak in rain-water containing bran, and in this 
wet state stretch the hides well on the stretch-bench. 

Twelfth. Now shave them as clean as possible on the flesh 
side, and especially carefully on the grain side, in order to 
remove the whole grain, which removal produces the elasticity 
which prevents the liability- to cracking. 



LACE LEATHER. 567 

Thirteenth, Then, finally, rub into the hides a mixture of one 
and one-half pound of lard oil, one-half pound of tallow, and 
one-eighth pound of fine flour for every ten pounds of hide 
(which process helps to produce smoothness and durability of 
the leather), let them dry, then stretch and smooth them well 
with a wooden stretcher, and now the hides are ready for use. 

Quick Tanning Process for Lace and Whip Leather. 

The method patented in 1875 by Bartenbach and Eichter, of 
Detroit, Mich., is as follows : — 

For making lace and whip leather the hides are cleaned after 
soaking, the hair being removed. Then put them in the follow- 
ing solution, enough being used to fairly submerge them : To 
twenty-five gallons of warm water add two pounds of alum, 
fifteen pounds of salt, one pound of sulphuric acid, two pounds 
of wheat bran, two ounces of dissolved sulphur. The hides are 
left in this solution for twenty to twenty-five minutes, after 
.which one ounce of vitriol, four pounds of salt, and two ounces 
of alum, dissolved in one-half gallon of water, are mixed with 
the solution, and the hides are left to remain in it twenty 
minutes longer. The hides are then taken out and well wrung, 
and hung up to dry in a dark, airy place. Those intended 
for whip leather, when dry, are moistened with a little water, 
and stretched upon a stretching-iron. Those intended for lacing- 
leather, after being well dried, are rubbed with a mixture of 
one pound of fish oil, one pound of tallow, four ounces of linseed 
oil, and two ounces of soap-soda in a gallon of hot water. 

Loescherh Method for Manufacturing Lace Leather. 

In 1876 H. Loescher, of Chicago, 111., patented the following 
method for manufacturing lace leather, the object claimed being 
to produce lace leather of greater strength and tenacity than 
that produced by treating skins with lime and acids. 

The first step in this process is to remove the hair from the 
hide by fermentation by subjecting it to a decaying process for 
a few days. The next step is to dry the skin to a flinty hard, 
ness ; and the last step consists in subjecting the dried skin to a 



568 



THE MANUFACTURE OF LEATHER. 



process of torsion and beating until thoroughly softened, when, 
it is claimed that it will have the toughness of rawhide, with 
the pliability of kid. 

Coupe's Stretching Machine. 

The machine for stretchiug leather shown in Figs. 266 to 268 
is the invention of Wm. Coupe, of Attleborough, Mass., who is 
an extensive manufacturer of lace leather. 

Fiff. 266. 





Fig. 268. 




Figure 266 represents a front elevation of Coupe's machine. 
Fig. 267 shows the same in central vertical transverse section, 
and Fig. 268 represents the stretcher-bar in perspective. 

As particularly shown in Fig. 266 the machine consists of the 
following devices : A pair of standards as at A JL', in which is 
mounted a shaft, as at B^ to which power is applied. Upon one 



LACE LEATHER. 569 

end on this shaft is a pinion, as at C, arranged to mesh with a 
gear, as at i), loosely mounted on one end of a roller as at E. 

The inner side of this gear D is provided with a clutch face 
or pin as at d^ for engagement with a clutch as at F, splined to 
the roller E^ and furnished with a slipping-handle as at 6^, so 
arranged as to be convenient of access to the operating attendant. 
The remaining parts of the machine consist of a narrow table 
or breast-beam as at H^ which is mounted in mortises as at a, in 
the standards A A\ and a stretcher-bar as at K^ likewise mounted 
in mortises as at a', and having its two working faces doubly 
inclined as at h k\ Fig. 268. 

The operation of the machine is as follows : — 

A hide is placed over the table or breast-beam iT, and one of 
its ends carried under the stretcher-bar K^ and secured to the 
roller E by the clamp e, the other end hanging free in front of 
the machine, as shown in Fig. 267. The operator now connects 
the roller E to the continuously-revolving gear D by means of 
the handle G and clutch F^ and the roller E slowly revolves, 
winding the hide around its surface, and drawing it over the 
friction table or beam II, and around the stretching-bar E^. 

When any part of the hide, the thickness of which is to be re- 
duced, or the wrinkled or fulled-up portion smoothed out, passes 
over the table or beam II, the operator who stands in front of 
the beam applies pressure by hand to the proper portions, 
thereby increasing the friction between the under surface of the 
hide and the surface of the bar H, and causing the onward 
movement of such portions to be retarded. The portions thus 
pressed upon are more severely stretched than other parts of 
the hide, and by proper manipulation by the attendant its thick- 
ness is rendered uniform, and it passes to the stretching-bar K 
in a smooth condition, having been longitudinally stretched 
upon the beam H. 

In passing over the bar K the hide is transversely stretched 
by the doubly-inclined sides k h\ from which it passes onward 
to the roller E, winding about the roller uniformly and smoothly. 
The machine is now stopped, the hide removed, another secured 
to the roller E, and the operations above described are repeated. 



570 



THE MANUFACTUEE OF LEATHEE. 



Tiddh Softening Machine. 

Figs. 269 to 277 show the machine invented by J. Tidd, of 
Woburn, Mass., which is much used for softening lace leather. 

Fig. 269 is a side, and Fig. 270 an end elevation. Fig. 271 
shows the under side of the cross-head G. Fig. 272 is a top 
view of the bed B. Fig. 273 is the under side of a grooved 
cross-head. Fig. 274 is the top side of a grooved bed. Fig. 
275 is a side view of a grooved cross-head, with a corrugated 
or serpentine rib Z, instead of the pins C. Figs. 276 and 277 
are end views of Figs. 273 and 274. 



Fig. 269. 



Fiff. 270. 




Fiff. 271. 



(O %"o° 



o o o o o 
O o o o o 



2) 



Fiff. 272. 



o°o°90o°oOoOo°o' 



Fig. 273. 



Fig. 276. 



^ 



The perforated bed B^ is secured to the top of a supportiug- 
beam K^ in combination with a yielding cross-head (r, and a 
series of pins c, projecting downward from the under side. 



LACE LEATHER. 



571 



Each perforation a in the bed B is directly under a correspond- 
ing pin in the cross-head. A shaft H, is arranged in bearings at or 
near the centre, and near the bottom of the framework, and on 
each end of this shaft is a balance-wheel /, outside of the legs h^ 



Fif?. 274. 



Fig. 277. 



Fig. 275. 



4 



and on the same shaft inside of and near one leg is a pulley A^ to 
receive the belt which drives the machine. Projecting outward 
from each of the wheels Z are crank-pins or wrist-pins ?", and 
the lower end of a pitman ^, connects with each pin i. The 
upper end of each pitman connects with the lower end of a 
vertical rod m, which passes freely through a hole in the beam 
K^ and extends upward through the cross-head G. These rods 
m are screw-threaded from their upper ends downward to a 
little below the cross-head (r, and the latter is connected- with 
the rods m by nuts d beneath the cross-head, and by similar 
nuts e above. The nuts d are for raising or lowering the cross- 
head to any desired point of adjustment, and the nuts e are to 
screw down or up, and increase, release, or diminish the action 
of the springs (/, which are arranged between the nuts e and 
the upper side of the cross- head (r, so as to allow the latter to 
yield when the leather is placed on the perforated bed, beneath 
the cross-head and the pins c, the downward motion of which 
brings the lower ends of the pins into contact with the leather, 
pressing, forcing, or bending certain portions of the leather, and 
in succession other portions, across the edges of the perforation 
o, thereby limbering and softening the leather to the desired 
degree, or in proportion to the time the leather is moved about 
between the perforated bed and the pins and cross-head while in 
motion or action. 



572 THE MANUFACTURE OF LEATHER. 

Instead of perforated bed and the pins, there are sometimes 
used a grooved bed and a grooved cross-head, shown in Figs. 273, 
274, 276, and 277, and either straight or corrugated or serpentine 
horizontally, as in Fig. 275, but the perforated bed and the pins 
for softening most kinds of leather and hides are preferable, as 
they require less power, and have a tendency to enlarge the side 
or piece of leather or hide, by the peculiar operation of the pins 
and perforations drawing in every direction ; whereas, in all 
previous modes of softening leather such as pounding the leather 
with a wooden mallet, when spread out on the tops of several 
pins promiscuously disposed, the leather was considerably con- 
tracted or reduced in size, and very imperfectly and unequally 
softened. 

This machine is driven by a belt from some rotating pulley 
on to the pulley A, which rotates the shaft IT and wheels or 
cranks /, through the medium of which, and the pitmen h and 
rods m, the cross-head G and pins c are moved up and down 
about two hundred strokes per minute. The leather or the 
hide is moved or fed along over the bed i?, while the pins c 
strike or press portions of the leather into the perforations; 
changing from one portion to another until the whole surface of 
the leather has been acted upon, and the entire side or piece of 
leather is well and perfectly softened. 



CHAPTEE XXXY. 

HORSE LEATHER FOR FOOT WEAR. 

The manufacture of horse hides for foot wear originated in 
■ Denmark, and from there it followed the coast of the Iberian 
peninsulas, and was largely developed in Hamburgh. There it 
took root immediately and was developed gradually to the high- 
est degree of perfection. 

From Hamburgh the art spread to Austria, Poland, the 



HOESE LEATHER FOK FOOT WEAR. 573 

Eusso-German provinces and Scandinavia, whicli have each 
manufactured some very handsome horse-leather footwear. 

England and France are also manufacturing this leather to 
some extent ; but in the United States there is but little done in 
this line of manufacture. At the Philadelphia Exhibition in 
1876 all other kinds of leather produced in this country were 
exhibited; horse leather being the only exception. 

The beam-house work is about the same for horse hides as 
for other hides. 

The lime work is reduced as much as possible, and it is desir- 
able to use only fresh and pure lime baths, so that the sides may 
swell as much as possible and be apt to produce leather. 

After having been properly limed the sides are unhaired on a 
well conditioned beam, wide and smooth. Sometimes two or 
three fleshed hides are spread upon the beam to bring them to the 
proper condition. The sides are next placed in clear water 
overnight, and are then green shaved and placed in a bate of 
hen manure, in which they usually remain for about four days, 
but this varies with the nature of the hide. The bating can be 
reduced to six or eight hours by using the England wheel shown 
in Fig. 112. 

The bate is then worked out by hand, and it is desirable to 
work the thin places very cautiously ; but at the same time the 
grain should be well cleansed. The sides after being allowed 
to remain overnight in clear water after the bate has been 
worked out, are then placed in the handlers and hung on sticks. 
The usual time which the sides remain in the handling liquors 
is six or seven days, and they are then laid-away twice in 
ground bark, both lay-aways extending through about seven 
weeks. 

Upon being removed from the second lay- away the sides are 
hung on poles and exposed to the open air to harden, and are 
then dampened and split; but the operation of splitting horse- 
hides by machinery is much more difficult than that for other 
species of hides, and requires considerable experience. 

In Hamburgh, Germany, where a large quantity of horse 
leather is manufactured, the splitting machine is not employed, 
the custom being to soak, unhair, and flesh the hides, and then 



574 THE MANUFACTUEE OF LEATHER. 

to cut the butt at once by taking off a few thicknesses with the 
fleshing knife. 

The sides split by the splitting machine are next flattened 
by having their shanks and bellies levelled oft' with a currier's 
knife. 

From this point the process of tanning and currying horse- 
leather is the same as has been described for the side of upper- 
leather in Chapter XXIX. 



CHAPTEE XXXYI. 

RUSSIA LEATHER — THE MANUFACTURE OF RUSSIA LEATHER — 
RUSSIAN METHOD OF PREPARING AND APPLYING THE MORDANT 
AND DYE — MANUFACTURE OF BIRCH OIL — ARTIFICIAL RUSSIA 
LEATHER. 

Section I. The Manufacture of Eussia Leather. 

EussiA leather is employed more for articles of luxury than 
of utility, it possesses an agreeable odor, and does not moulder 
under the influence of dampness, nor is it liable to be destroyed 
by insects, which often ravage other leathers, the empyreumatic 
oil used in dressing it being a preventive. 

But, as has been stated on page 67, its use for book-binding 
in the numerous public libraries of this country is being rapidly 
superseded by red-colored Morocco leather, which is attractive, 
more durable, and less costly. 

Eussia leather is much used in the manufacture of pocket- 
books, jewelry cases, handkerchief cases, and other toilet arti- 
cles, also for albums, cigar cases, travelling bags, etc. 

It derives its name from the country whence it originated, 
and where it is more especially manufactured ; the method of 
which has only of late extended across the border of the Eus- 
sian empire. 



RUSSIA LEATHER. 0/0 

The Centennial Exhibition at Philadelphia in 1876 did not 
contain a single exhibit of this leather by a Eussian manufacturer. 
Eussia, at the Paris Exhibition of 1878, had only one manu- 
facturer displaying samples of this specialty, M. T. Savine, who 
obtained a gold medal. 

T. P. Howell & Co., of Newark, IST, J., were the only manu- 
facturers in the United States who exhibited Eussia leather at 
the Centennial Exhibition. 

The method of manufacturing this leather we shall describe 
as it is conducted in the United States, for the reason that the 
machines here employed are so much superior to those used in 
Eussia that an article almost equal to the native Eussia leather 
is produced, and in a much shorter time. 

The hides used in the production of this leather are generally 
cow or steer hides, and large calf-skins, seldom goat or sheep- 
skins. 

In tanning, the first operations, such as soaking, unhairing, 
fleshing, etc., are conducted in the same manner as for other 
kinds of leather. 

The swelling of the hide is one of the essential points for its 
successful manufacture, and is proceeded with in the following 
manner: For one hundred cow or steer hides take twenty-two 
pounds of rye flour and ten pounds of oat flour, and knead with 
yeast and a little salt. 

Allow this dough to ferment, and then thin with sufficient 
water to immerse the one hundred hides, which are left in this 
preparation for forty-eight hours, and when they ares ufiiciently 
swollen, the hides are placed in a tepid solution of willow and 
poplar barks. The hides are handled in this solution, twice a 
day, for at least eight days. They are next immersed in a liquor, 
the tanning ingredients of which are composed equally of oak, 
pine, and willow barks, and in this liquor they must also be 
handled at least twice a day. After eight days the last-named 
liquor is renewed and the hides are hardened and split, and then 
again placed in the liquor for another eight days, care being- 
observed to handle as before. After this time the hides are 
sufficiently tanned. 



576 THE MANUFACTURE OF LEATHER. 

The period of tanning can be considerably shortened by using 
a revolving-wheel, placed over the tan-vat to gently agitate the 
liqaor, such as the England wheel shown in Fig. 112. 

After being tanned the hides are cut into sides, and scoured 
and then rinsed in clean water and allowed to drip and dry. 
The sides are then slightly dampened and allowed to temper for 
two days and then greased with a mixture of birch oil and seal 
oil, two-thirds of the first and one-third of the second, according 
to the thickness of the leather. 

For heavy leather a coat of this grease is applied to the grain 
side. The leather is then thoroughly greased on the flesh side, 
and afterwards fulled. The leather is next set out, then 
whitened, and finally boarded, and when well dried it is pre- 
pared for dyeing. 

Before dyeing, the sides are submitted to an albuminous 
solution, which acts as a mordant to make the color penetrate 
more easily. 

The leather is dyed black or red, but the latter color is most 
used. 

The dye is made of a decoction of sandal wood, the quantity 
of whicli must be judged by the operator, who obtains the cor- 
rect shade by repeated essays on small fragments of leather. ~ 

Sandal wood and cochineal give a richer color, and are some- 
times used. 

The leather must be dyed in several coats, taking care that 
the preceding one is well dried before applying another coat, 
the dye being applied with a brush to the grain side. 

After dyeing, the leather is again impregnated with a mixture 
of birch oil and seal oil, which must be made to penetrate as 
much as possible, by rubbing energetically with a flannel rag 
on the grain side. 

As a mordant in Russia they use chloride of tin prepared in 
the following manner : Take of ounces of azotic acid, heat it 
very slowly under a chimney having a good draft so as not to 
be indisposed by the emanations of the acid, pour in this hot 
solution, stirring it meanwhile with a glass or a wooden stick, 
1 pound and 2 ounces of salt of tin. This operation must be 
done in the open air or vmder the influence of a strong draft, so 



EUSSIA LEATHEE. 577 

as not to inhale tlie deleterious vapors of the azote, which are 
excessively dangerous. 

Stirring must be continued with caution so as to allow the 
unwholesome vapors to escape ; when the mixture begins to 
whiten add 4J ounces of smoking hydrochloric acid, stirring 
carefully for a few moments. 

The liquor must be cooled and put in hermetically closed 
bottles, to be kept in a cool place, and before using this liquor 
it must be diluted in a volume of from 12 to 15 times its own 
weight of pure water. 

The leather being prepared and cleansed from all foreign 
substances, the mordant is applied very briskly and uniformly 
with a brush. 

As coloring matter in Russia they use 1 pound and 2 ounces 
of sandal wood boiled for an hour in If gallons of pure water. 
This liquor is filtered and 1 ounce of prepared tartar and soda 
dissolved in it. 

This mixture is boiled for an hour, and it is left standing for 
a few days before using it, as it is then stronger. 

The sides destined for black dyeing are only oiled on the flesh 
side, which must be dried with a woolen rag, leaving the grain 
half-moist, and irreproachably neat. 

The leather is submitted two or three times to the mordant, 
according to its thickness, and then dyed as many times with 
the warm dye, the temperature of which must be raised if 
necessary ; i, e., the dye must only be applied while warm, 
and if the operation takes too much time according to the 
number of skins, the dye must be kept at the proper tempera- 
ture. 

The application of the mordant and dye is done with a 
brush by rapidly spreading the liquid which is poured on the 
leather. 

Rapidity in this operation is necessarj'- in order to spread the 
dye equally on the whole surface of the leather and to insure 
the same shade on all its parts. 

The first coat of color is applied immediately after the mor- 
dant and while the leather still retains some of its moisture ; 
37 



578. THE MANUFACTUEE OF LEATHER. 

in this manner the dje takes more easily and there is less risk 
of shading. 

It is desirable for the good execution of this work to have 
two men operating together ; the first applying the mordanty 
and the second the color immediately afterward. Should the 
color not be uniform another coat is applied at once with a 
lighter solution. 

■ This red color lasts as long as the leather itself and does not 
damage it, whatever may be the time of its stay in the ware- 
house. 

After the dye the leather must be slightly moistened on the 
flesh side with some tan juice and dried, and then grained. 

The red Russia leather acquires a brilliant appearance when- 
its colored side has been coated with gum tragacanth solution 
by means of a sponge ; this gelatinous water must neither be too 
thick nor be applied in too large a quantity. 

For graining the hides the same methods are followed as for 
the manufacture of Morocco leather; but instead of being 
" straight grained" or " pebbled" the finish is a diamond-shaped; 
grain. 

A new graining machine, especially for Eussia leather, was: 
lately invented by Towein, who, unfortunately, died when he: 
was finishing it. 

However, his work survives him, and his graining machine is 
in use in large French establishments and its success is com- 
plete. 

Slack colored Russia leather is prepared in the same manner- 
as has been described, but is stained by the application of ace- 
tate of iron, aniline and other blacks being also used. 

For a method of dyeing Russia leather with aniline colors, see 
Chapter XLIII., Section VIII. 

Section II. Manufacture of Birch Oil. 

This oil is commonly called Kussia oil, but, notwithstanding 
this name, the bark of the birch tree of all countries will pro- 
duce it, and it is in the whitish, membranous epidermis of the 



RUSSIA LEATHER. 579 

bark that the oil exists, and this should be carefully separated 
from the ligneous or woody matter. 

The bark is considered preferable when it has been freshly 
gathered. 

If the distillation of the oil is done in the spring, some birch 
buds are mixed with the bark ; a more limpid oil is thus ob- 
tained and its odor is more penetrating and delicate, as it re- 
sembles a little the flavor of the rose. This mixture also facili- 
tates the separation of the oil, which when thus prepared is of 
a lighter color, from the small quantity of soot it contains. 

Many systems are followed to distill the birch oil ; some of 
them, very simple, are within the capabilities of any one ; the 
others, more elaborate, require the science and complicated 
stills of the chemist. This oil can be readily obtained by dis- 
tilling the bark in iron cylinders placed horizontally in a 
furnace. 

In each of the methods of distillation, to be hereafter described 
separate the birch oil from the tar, acid, etc., underlying it, and 
keep it in a glass stoppered bottle or some other close vessel. 

The following is a simple method for distilling this oil: 
Above any kind of receiver place an earthen pot of a conve- 
nient capacity with a hole pierced through its bottom ; fill the 
pot with the bark, put fire to the bark, and cover the earthen 
vessel with another of similar capacity, also having a hole in 
its bottom. The bark burns slowly, the smoke and the hetero- 
geneous products of this kind of distillation evaporate through 
the aperture in the upper vessel, and the oil runs through the 
lower opening into the receiver below. 

Another method, which is that of Fischerstroern, is a little 
different from this, although based on the same principles. 
To carry it out, fill an iron caldron with bark and cover with 
a convex lid, in the middle of which a hole is made, for the in- 
troduction of an iron tube ; above this caldron another one is 
placed and the two secured together, the second caldron hav- 
ing a hole in the bottom, through which passes the iron tube of 
the first caldron, but which must not touch its bottom. 

The two caldrons, suitably united, must be hermetically closed 
by means of clay. They, are then inverted and half buried in 



580 



THE MANUFACTUEE OF LEATHER. 



the ground, tlie one containing the bark being uppermost, and 
it is daubed over with a mixture of sand and clay. A large 
wood fire is built around this iron caldron, so as to bring it to 
a white heat. When everything is cooled the distillation is 
complete and the caldrons may be opened. 

In the upper caldron there will be a fine coal powder, and 
in the other the products of the distillation, i. e., the birch oil 
floating, underlaid with a little tar, upon a slight layer of pyro- 
lignpous acid. 

By.Grouvelle and Duval-Duval's process, the material is in- 
troduced into a copper still, similar to those used to distill wood 

in the manufacture of acetic acid. 
The receiver is so adapted as to be 
immersed in water in which the 
gaseous products are condensed, 
and, as in the manufacture of acetic 
acid, the resulting products are 
pyroligneous acid, tar in larger 
quantity, and the oil more colored, 
and less abundant. 

The oil may be obtained nearly 
colorless by rectification, but this 
is not useful, unless the oil is in- 
tended to be employed on deli- 
cately colored leather. 

By repeating the distillation 

per descensum, Payen ascertained 

that with a simple apparatus it is 

possible to obtain an oil less colored and in the proportion of 

one-fifth more, at a temperature less elevated. 

To construct this apparatus, which is shown in Fig. 278, a 
hole is made in the bottom of an earthen furnace A, large 
enough to receive the neck of a matrass M. The furnace is 
supported by two bricks placed upon the plank, which is also 
perforated so as to admit of the passage of the neck of the 
matrass, and which rests upon the trestles C, G. The matrass 
is filled to its utmost capacity with the epidermis of birch bark ; 
it is inverted and passed through the furnace and the board. 




ARTIFICIAL RUSSIA LEATHER. 581 

Then the neck is luted and placed in the position seen in the 
figure, being supported by sand thrown into the bottom of the 
furnace as high as F^ F, and in order to expose the matrass to a 
uniform heat, it is protected by inverting over it an earthen 
hemispherical vessel or crucible. Around this, burning coals 
are placed, and the fire is kept up through two lateral openings, 
D, D, the dome /, K, L being placed upon the furnace top. 
Condensed water first trickles from the mouth of the matrass 
into a vessel placed beneath, and this is succeeded by drops, and 
then by a constant stream of an amber colored oil. After a 
time this ceases, and it is necessary to applj^" heat lower down 
to the neck of the matrass, so as to cause the discharge of the 
last portions of all tarry matters which have condensed in it. 

The products obtained by the distillation of one hundred parts 
are as follows: — 

A brown oily matter, light fluid empyreumatic, soluble in 

ether 70.00 

Thick dark brown tar containing a little oil . . . 5.00 

Water acidulated with pyroligneous acid .... 10.00 

Light spongy charcoal . . . . . . . 12.50 

Gases .......... 2.50 

100.00 

Section III. Artificial Eussia Leather. 

Artificial leather has been usually made of textile fabric 
coated with vulcanized rubber, and has been known in the trade 
as "rubber cloth." Sometimes it is made of textile fabric 
coated with varnish, and bears the name of "enamelled cloth." 
It has also been made of paper-pulp coated with varnish, and is 
then known as " leatherette." The appearance of leather in all 
these cases is imparted to the artificial compound by giving it 
the grain of real leather. The article, however, when partly 
composed of vulcanized rubber, has an unpleasant odor when 
subjected to a high temperature. When made of paper-pulp 
and varnish it does not long retain the color given to it by 
dyeing. In all these artificial leathers the coating cracks and 
peels off' during wear, and none of them are pliable like real 
leather. If a cut is made in the material, it is liable to split its 



582 THE MANUFACTURE OF LEATHEE. 

entire length. The appearance or odor of Eussia leather has 
never heretofore been given fully to artificial leather. 

The object of the present method, patented by E. M. Freely, 
is to obviate the defects in ordinary artificial leather by produc- 
ing an article which will have the appearance and peculiar odor 
of Eussia leather, which will be pliable, retain the outside 
coating and dye in ordinary wear, and not be liable to tear un- 
less much strength be exerted in the eflbrt. To accomplish 
this take the ordinary imitation leathers, which are well-known 
articles of commerce, and steep them in a solution made of fifty 
pounds of bark of oak, fifty pounds of bark of hemlock, fifty 
pounds of bark of sumac, one pound of bark of willow, and nine 
hundred gallons of water. While the material is yet damp 
smear on the outer or leather side a solution made of a large 
tablespoonful of Eussian jachten extract dissolved in a pint of 
alcohol and half a pint of ether. This, it is claimed, renders the 
material pliable and gives it the odor of Eussia leather. It is 
then rolled up into bundles with the outer or leather side in and 
laid away to dry. When it has thoroughly dried, it is ready 
for use. 



CHAPTEE XXXVII. 

ALLIGATOR LEATHER. 

At present, the most fashionable material for small valises, 
satchels, portmonnaies, cigar cases, etc., is the skin of the 
American alligator, and in addition to uses enumerated it is also 
used for uppers of ladies' and gentlemen's shoes. 

In all the Gulf States, from Florida to Texas, these sauroid 
fish are hunted to supply the demand. 

Alligator leather has been in vogue for a long time ; but 
during the past five years the slaughter of the alligator has been 
prosecuted with great activity. 

These skins are usually packed for shipment in barrels and 
are green salted. The salting is usually poorly done, and if the 



ALLIGATOR LEATHER. 583 

skins are allowed to remain too long in the barrels thej^ become 
heated and the grain sides thereby become so injured that the 
skins have to be finished into second class leather. 

Only the skin from the belly and sides is used, the back with 
its heavy coat of scales is cut out and thrown away as worthless. 

All the skins show great uniformity, being of a bluish black 
hue on the sides and a peculiar bluish white under the belly, 
and each skin is curiously checkered in oblong divisions, which 
being separated by intersecting grooves, and wrinkled, give the 
peculiar appearance seen in all alligator leather. 

The trade in these skins receive them of all sizes from three 
feet up, the average prices paid at New Orleans, La., for these 
skins ranging from fifteen cents each for the smallest to about 
one dollar for the largest. The skins most in demand are about 
seven feet long. 

The skins of the monster alligators ranging from ten to fifteen 
feet long are not much desired. Under the continual destruc- 
tion of alligators the supply is rapidly diminishing, and it is now 
but a question of a few years when it will be impossible to 
obtain these skins at a price that will justify their general em- 
ployment. 

To supply the demand for cheap articles, imitation alligator 
leather is now being largely produced. 

The alligator leather of this country and the kangaroo leather 
of Australia are similar in the respect that they both depend 
upon wild animals to supply the material for their manufacture, 
and the business is therefore to some extent precarious. 

At the place of shipment the skins from young, middle-aged, 
and old alligators are thrown promiscuously into barrels, and 
the first step when the skins arrive at the tannery is to assort 
the small and medium sized from the larger ones, which are 
kept separate. 

The skins are then thrown into vats containing clear, cold 
water, and in these soaks the smaller skins remain about two 
days and the large ones four days. 

They next go into vats of lime, which should not be so strong 
as for depilating hides or skins, and in the limes they remain 
from eight to fourteen days, according to the size of the skins. 



584 



THE MANUFACTURE OF LEATHER. 



¥is. 279. 



Bach day the skins are reeled into stronger lime, great care 
being observed not to rot the tender portion of the skins during 
this swelling. 

The bate of hen manure, into which the skins next pass, is 
made quite weak, and in this bate the skins are gently agitated 
by means of the usual England wheel shown in Fig. 112, the 
period for which they remain being from ten to fifteen hours, 
according to the size of the skins. 

They are next cleansed in a wash wheel, and then thrown 
into a vat containing hemlock liquor of about 4° strength, and 
every other day the skins are shifted into 
stronger liquor until at the end of about 
twenty days it has been increased to about 
20° strength. 

A gentle agitation of the tanning liquor 
during the last twelve days is very bene- 
ficial, as it aids in the more thorough 
tanning of the skins, and prevents the 
settlement of the sediment of the liquor 
into the creases of the skins, which is 
liable to rot the tender portions, especi- 
ally those of young alligators. 

After being subjected to the tanning 
process just described, the skins are hung 
in the open air to harden. 

They are then carried into the finish- 
ing room, and eight or ten skins are piled 
one upon the top of another and placed 
in a clamp, the flesh side of the skins 
being uppermost. 

The flesh sides are then softened by 
the operator with a tool similar to that 
shown in Fig. 279, the object being to 
throw up the rougher portions, which 
are then lightly cut off with a currier's 
knife. 
If the skins are intended to be manufactured into upper-leather, 
tbey are again placed in the tanning liquor of 8° or 10^ strength, 




PATENT, JAPANNED, OR ENAMELLED LEATHER. 585 

and in this they remain for six or eight days, during which 
period they are gently agitated. 

After being removed from the final tanning liquor the skins 
are scoured by hand on a slate table, first on the flesh and next 
on the grain side, the tools used being the scouring brush, 
stone, and slicker. 

After being scoured the skins are placed in the air to harden, 
and when not quite dry they are carried into the shop and 
stuffed by hand, tallow, fish oil, and a small quantity of rosin 
being used. 

They are next " set out," and are then carried to the finishing- 
room and blackened on the grain side with a preparation of log- 
wood and copperas. 

They are next glassed by hand, and if a gloss is desired they 
are " pasted over the black" and hung up in the finishing room 
to dry over night. 

In the morning the skins are re-glassed, and immediately 
finished by gumming them over on the grain side with a prepa- 
ration of gum tragacanth, and are then measured and ready for 
market. 

The skins not intended for the manufacture of upper-leather 
are not blacked, but are finished in their natural color, which is 
a yellowish-brown, and are used for satchels, pocket-books, etc. 

A method for manufacturing Japanned leather in imitation 
of alligator skin is described in the following chapter. 



CHAPTEE XXXVIII. 

PATENT, JAPANNED, OR ENAMELLED LEATHER. 

The hides used for the manufacture of patent, japanned, or 
enamelled leather are the heaviest, largest, and finest slaughter 
hides that can be obtained ; those from the "Blue Grass Region" 
of Kentucky are most esteemed for this variety of leather. 

The material employed for tanning the hides is usually a 



586 



THE MANUFACTURE OF LEATHER. 



mixture of oak and hemlock bark, making what is known as 
union tannage. 

The soaking, liming, unhairing, fleshing, and bating are the 
same as have been described for the other varieties of leather. 
The unhairing and fleshing are accomplished by hand, and the 
England vat and wheel shown .in Fig. 112 is used for agitating 
the hides while in the bate of hen mannre, and thus hastening 
the operation. 

After the hides have been properly bated a different method 
is then employed for " working out the bate" from that which 
has been heretofore explained. 

Upon removal from the bate the hides are worked in a hide- 
mill through which passes a stream of water. The hides are 
then laid upon a beam and carefully worked over with a bate 
stone, shown in Fig. 280. 

Fig. 280. 




When the hides have been properly worked with the batC; 
stone, they are placed in a wash wheel and worked for about 
twenty minutes, after which they are in condition to go into the 
" handlers" to be properly swelled for the reception of the tan- 
ning liquor. 

The hides are not laid away in ground bark, as has been de- 
scribed for sole and upper leather ; but are placed in vats hav- 
ing a circular bottom, and above which there is placed a revolv- 
ing wheel which agitates both the tanning liquor and the hides ; 
there are usually a number of these vats in a line, as shown in 
Fig. 281. 

The wheels are worked for about fifteen minutes each hour, 
and when about one-third tanned the hides are removed from 
the tanning liquor and a buffing is taken off of each hide, which 



PATENT, JAPANNED, OR ENAMELLED LEATHER. 587 



is sometimes done with a currier's knife and at other times with 
a splitting machine. 

After the buffing has been removed from the hide it is next 
split by a large belt-knife splitting-machine, shown in Figs. 132 



Fiff. 281. 




to 135, and is divided into three parts. The grain side is enam- 
elled in various colors, and is used for carriage tops and uphol- 
stering. The middle is finished for splatter-boards and other 
trimmings for carriages, and also for harness use, and the flesh 
split is used in shoe manufacturing and for other purposes. 

The split portions are next placed in a drum and strong 
gambler liquor poured over them, and in this wheel they are 
worked for about ten or fifteen minutes, the gambler liquor 
and working being to prevent the " glazing or crusting" of the 
partially tanned leather after it is replaced in the tanning liquor. 
After being fully tanned the leather is placed upon a table as 
shown in Fig. 137, and scoured, or the scouring may be done by 



588 



THE MANUFACTURE OF LEATHER. 



machinery, the Lockwood and improved Fitzhenrj machines, 
which have been explained in Chapter XXI., being sometimes 
employed on this variety of leather. 

The hides are next stretched after being scoured, and a good 
frame for stretching leather is shown in Figs. 282 to 286, and it 
is the invention of Charles P. Oliver and Theodore P. Howell, 
of Kewark, N. J. 

This device possesses the merit of unusual simplicity and 
cheapness of construction, and also is susceptible of opera- 
tion without removing the frame from its pendent position from 
the supporting-bars. 

Fig. 282 is a representation of a top view of Oliver and 
Howell's Machine. Fig. 283 is a vertical transverse section of 
the same. Figs. 284, 285, and 286 are details of the same. 

Fig. 282. 






wn 



Fig. 283. 



^3_E^^2fc 



A represents the upper and B the lower cross-bar of the 
stretching-frame, and Vindicates the sides. On the front sides 
of the bar C, or upon the sides of such bars, are affixed per- 
forated plates, marked a. These perforated plates are adapted 



PATENT, JAPANNED, OR ENAMELLED LEATHER, 589 

for use upon wooden upright bars; but in case such bars be made 
of metal, the plates may be dispensed with, and the cross-bars 
themselves be perforated. The cross-bar A is constructed with 
a rounded upper surface, to adapt it for holding the centre of 

Fig. 284. Fig. 285. 




K 



1 ^ 



J 



Fig. 286. 



(g= 



the hide, inasmuch as this apparatus is designed for attaching 
both flanks or sides of the hide to the sliding bar D. The letter 
D represents the sliding or stretching bar, which is arranged 
with reference to the bars A and Cin the manner shown. The 
letter c indicates the short arm of a joint attached to the sliding 
bar D, and /indicates the long arm thereof attached to the bar 
B, each connection being made with a suitable pivot-pin or 
hinge. These two arms of the joint are united by a tongue- 
and-groove joint, as shown on Fig. 283. It will be observed 
that the end of the sliding bar D ig slotted to provide for hold- 
ing the forearm of the joint and allow the movements thereof. 
The letter y indicates a quadrangular wrist firmly attached to 
the short arm of the joint. It is preferable to cast this arm and 
wrist in one piece of metal. The letter ^represents a wrench, 
the head of which is adapted to fit upon the wrist y. 

To operate this device, tack the moist hide to the sides of 
bar Z>, allowing the centre thereof to rest upon the oval upper 
surface of bar A, and place the wrench head upon the wrist y. 
Then turn the wrench downward, bringing the two arms of the 
joint toward or beyond a right angle, thereby increasing the 
distance between the bars A and D. When the skin is suffi,- 
ciently stretched, place a pin above the bar D in one of the 



590 THE MANUFACTUEE OF LEATHER. 

apertures of the perforated plate, and permit the skin to dry, or 
be manipulated, as the operator may see fit. 

The hides are allowed to become perfectly dry on the frames 
before applying the compositions which are to finish the patent, 
japanned or enamelled leather. The first operation consists in 
treating the. hide to a mixture which is. intended to close .as 
much as possible the pores of the leather and thus obtain a 
ground ready to receive the varnish. The ground-laying mix- 
ture may be composed as follows : — 

White lead . . . . .10 pounds. 

Litharge . . . . . . 10 pounds. 

Linseed oil ..... 14 gallons. 

These materials are boiled together until they are reduced to 
the consistence of a syrup, and then there is added chalk or 
ochre, according to circumstances, and the material is then 
spread upon the hide with a steel tool called a " railike." 

The frame containing the hide is then placed in the driers 
with the face side downward as shown in Fig. 287. The driers 
have coils of steam-pipes arranged on the bottom and around 
the sides, through which there is a constant circulation of 
steam when all the racks are filled with frames containing the 
prepared hides. The steam to each drier is controlled by a suit- 
able valve, and when it is desired to admit the heat to the drier, 
the door is placed to the larger front opening, and the valve 
opened so as to give a temperature of about 80° F. to the interior 
of the drier, and from this point the heat is gradually increased 
to 160° F., which is about the greatest heat that the fibres of 
the leather will stand without injury. Sometimes it is desirable 
to subject the leather to a greater heat than 160°, and in that 
Case the fibres are protected by saturating the leather with a 
solution composed of: — 

Alum . . . . . . 2 oz. 

Borax . ... . . 2 oz. 

Water . . . . . . 1 gallon. 

The leather is immersed in the above compound for about 
two hours, and when nearly dry it is stretched in the usual 



PATENT, JAPANNED, OR ENAMELLED LEATHER. 



591 



manner on frames, and after japanning, it is placed in the oven as 
has been described, and the heat can then be gradually increased 
from about 80° to 230° or 250° F. 

The borax may be dispensed with if desired, as it is not 
absolutely necessary to produce the effect ; but is used to pre- 
vent re-crystallization of the alum. The leather is kept in the 
driers from six to ten hours, or until the composition is com- 
pletely matured and the surface perfectly dry. 

The ground is next rubbed with pumice stone to keep the 
surface smooth, and is then coated with from three to five layers 
of linseed oil colored with ivory black, and containing sufficient 
spirits of turpentine to enable it to flow evenly over the surface. 
After each application the hide is dried as has been described, 

■ " ■■ Fig. 287. 




and it is after each application except the last one rubbed over 
with fine tripoli or pumice stone, applied with a piece of flannel. 



592 THE MANUFACTUEE OF LEATHER. 

A varnisli is also used which is composed as follows : — 

Spirits of turpentine .... 10 lbs. 

Thick copal varnish . . . . 5 " 

Asphaltum . . . . . . J lb. 

Linseed oil . . . . . .10 lbs. 

The asphaltum can be replaced by an equal quantity of 
Prussian blue, or ivory-black, according to the finish desired, 
the one giving a reddish, and the other a blackish tint. 

The varnish is allowed to remain in the finishing room for 
fifteen or twenty days before being applied to the surface and 
is laid on with a brush as shown in Fig. 287, and the room in 
Avhich the varnishing is conducted is kept dampened and free 
from dust, similar to a coach-finishing or varnishing room. 

The variety of leather is not softened or boarded until it is 
japanned and been perfectly dried ; but in 1871 Franklin S. 
Merrill, of Boston, Mass., patented a process for boarding the 
leather while it is wet, by which manner of boarding it is claimed 
that the japanning is not cracked. 

Renewing the Surface of Japanned Leather. 

In 1863 Wm. Hoey patented in England the following com- 
pound for renewing the surface of japanned leather: Two 
ounces of paraffine, or rock oil, or a mixture of both in any pro- 
portion, to which are added one-quarter of a drachm of oil of 
lavender, one-quarter of a drachm of citrionel essence, and one- 
half ounce of spirits of ammonia. The mixture is applied 
lightly to the surface of the leather. 

Preparing the Cut Surface of Split Leather for Manufacturing 
Japanned or Enamelled Leather. 

The common way of buffing the hide or preparing it for 
japanning or enamelling is either by shaving off" the inequalities 
with a currying-knife, as explained on p. 586, or by taking of a 
light bufl&ng with the regular splitting machine. This light buff- 
ing, when finished, is of little value, bringing from one to three 
dollars. The way japanned or enamelled leather is often treated 
is by applying all the coats of the composition to the leather after 



PATENT, JAPANNED, OR ENAMELLED LEATHER. 593 

being tanned, and when perfectly dry on the frames. The 
naphtha or turpentine in the composition is then absorbed by 
the dry leather, and it becomes dry and harsh ; but by applying 
the iEirst coat of the composition when the leather is wet and the 
pores are filled with tan-ooze, the naphtha or turpentine evapo- 
rates before the leather becomes dry, and is not absorbed by it, 
and the leather is left soft and flexible and more easily worked. 

If a heavy buf&ng be taken off, it leaves the surface fibrous and 
coarse, and it is necessary to have a smooth surface to finish 
on — that is, to japan or enamel. 

Stephen J. Patterson, of Bridgeport, Conn., in 1883 patented 
the following method for forming an artificial grain on the hide 
after it has been buffed or split with a regular splitting-machine. 

This process of treatment applies equally well to light buffings 
or splits, but is especially adapted to heavy ones by largely 
increasing their value. 

Patterson's improvement is as follows : When the split hide 
comes from the tan-liquor after the tanning operation is com- 
pleted, it is slicked out on a table and a light coat of oil spread 
over the surface with a sponge or soft brush. Then it is tacked 
on a frame, and while still wet the fibre or nap of the freshly- 
cut surface is brushed down smooth in one direction with a flexi- 
ble bristle brush (like a shoe-blacking brush, but larger), which 
simply gives direction to the fibre or nap; and then there is 
applied, while the hide is still wet, with the same brush or with 
a sponge, rubbing in the same direction, a coat of composition 
made from linseed oil boiled down to a jelly and reduced with 
naphtha or turpentine to the proper consistency. After this 
application repeat the brushing operation as before. The hide 
is now left to dry, and when dry the composition holds the fibre 
or nap in place, and the leather has a smooth surface to japan 
or enamel. When dry it is finished the same as other japanned 
or enamelled leather. The hide is not dubbed with a mixture 
of cod oil and tallow or other grease, as in the ordinary method 
of preparing heavy leather. For shoes and harness only a light 
coat of oil is applied as stated. It is buffed or split with the 
splitting- machine when about one-third tanned. 

For treatment by this process, Mr. Patterson takes off a heavy 
38 



594 



THE MANUFACTURE OF LEATHER. 



buffing with the largest size improved "Union Splitting- 
Machine," shown in Fig. 227, making a buffing about three- 
fourths the size of the hide. This is thick enough to japan for 
shoe-leather or similar purposes, and will bring from four to 
eight dollars when finished. The extra expense will not exceed 
one per cent, of the cost of the hide. 

Japanned Leather in hnitation of Alligator Shin. 

The object of this process, which was patented bj Franklin 
S. Merritt, of Boston, Mass., in 1871, is to produce japanned 
leather in imitation of alligator skin. 

The leather is prepared by the ordinary process of currying 
for patent or enamelled leather. Afterward it is coated with a 
composition of linseed oil boiled with driers, viz., litharge, burnt 
or raw umber, sugar of lead, sulphate of zinc, Prussian or Chi- 
nese blue, mixed with naphtha, benzine, spirits of turpentine, or 
camphine, with sufficient lamp or ivory-black to give it color- 
ing. 







Fig. 288. 




/ ux vv\^ 




W^fl^^ 


W^ 


^ 




^M\K' 


§M 






^ 


% 



Fig. 289. 



The leather, after being coated with several layers of the 
composition, each being dried before the next is applied, is 
rubbed with pumice-stone to give a smooth surface to the coat- 
Finally the last layer is applied and dried without rubbing 



ms 



PATENT, JAPANNED, OR ENAMELLED LEATHER. 595 

with pumice-stone, the whole making, thus far, what is usually 
called " patent or enamelled leather." The leather in this state 
is next wet sufficiently to soften it to admit of it receiving and 
retaining the impression of the die or rollers. Next the sheet 
of leather is passed between rollers or dies, or compressed by 
the same, so as to emboss it with the required figure or series 
of convexities. Next it should be softened while wet by 
" boarding," or by any other mode of effecting such as usually 
adopted by leather dressers and then dried. 

Figure 288 represents a face view, and Figure 289 a section 
of a piece of leather made as described. 

"When finished it may be used for many purposes in the arts, 
particularly in the manufacture of hand-satchels, shoes, etc. 

Substitute for Patent Leather. 

It has been proposed to make a substitute for patent leather 
by applying to the surface of the usual split hides employed for 
patent leather thin sheets of zylonite or a similar substance of 
a proper color. The zylonite is applied to the leather by dis- 
solving one side of the sheet in any of the well-known solvents 
and subjecting the same to pressure by passing the leather with 
the zylonite between a pair of rollers. 

A solvent such as collodion is then applied to the exterior 
surface of the sheet of zylonite, and the leather is progressively 
passed between a pair of rollers or compressing surfaces in con- 
tact with a plate of glass until the zylonite will be as finely 
polished as the surface against which it has been compressed. 

List of all Patents for Methods for Manrfacturing Enamelled, Japan- 
ned, and Patent Leathers, issued hy the Government of the United 
States of America, from 1790 to 1883 inclusive. 



No. 




Date. 




Inventor. 


Eesidence. 


12,226 


Jan. 


9, 


1855. 


H. L. Hall, 


Beverly, Mass. 


13,819 


Nov. 


20, 


1855. 


T. P. Howell and 
F. L. Blanchard, 


Newark, N. J. 


19,583 


Mar. 


9, 


1858. 


J. Rose, 


Newark, N. J. 


42,584 


May 


3, 


1864. 


F. Longhurst and 
A. L. Murdock, 


Boston, Mass. 


58,733 


Oct. 


9, 


1866. 


J. L. Newton, 


Boston, Mass. 


70,176 


Oct. 


29, 


1867. 


J. W. Dawson, 


Newark, N. J. 



596 



THE MANUFACTUKE OF LEATHER. 



No. 


Date 










Inventor. 


Kesidence. 


114,586 
115,083 

282,664 


May 9, 
May 23, 
Ang. 7, 


1871. 
]S71. 

1883. 


} 


F. 

S. 


s. 
J. 


Merritt, 
Patterson, 


Boston, Mass. 
Bridgeport, Conn 


289,241 


Nov. 27, 


1883 




J. 


B. 


Edson, 


Adams, Mass. 



List of all Patents for Apparatus for Stretching Leather, issued hy the 
Government of the United States of America, from 1790 to 1883 
inclusive. 



'So. 


Date. 


Inventor. 


Residence. 


22,893 


Feb. 


8, 1859. 


A. W. Roberts, 


Hartford, Conn. 


28,271 


May 


15, 1860. 


J. H. Haskell, 


Baltimore, Md. 


59,292 


Oct. 


30, 1866. 


W. Strevell, 


Jersey City, N. J. 


66,131 


Jnue 


25, 1867. " 






Reissues 






• J. W. Danson, 


Newark, N. J. 


2,790 


Oct. 


29, 1867. 






2,791 


Oct. 


29, 1867. . 






66,565 


July 


9, 1867. 


V. Colvin, 


Albany, N. Y. 


67,431 


Aug. 


6, 1867. 


T. P. Howell and 
C. P. Oliver, 


Newark, N. J. 


67,996 


Aug. 


20, 1867. 


A. Marsli, 


Newark, N. J. 


69,327 


Oct. 


1, 1867. 


W. Dunn, 


Newark, N. J. 


69,630 


Oct. 


8, 1867. 


J. F. Coburn, 




69,633 


Oct. 


8, ]867. 


J. F. Connelly and 
W. B. Hugbes, 


Newark, N. J. 


77,615 


May 


5, 1868. 


T. P. Howell and 
C. P. Oliver, 


Newark, N. J. 


82,063 


Sept. 


15, 1868. 


W. R. Andrews and 
R. Dingwell, 


Newark, N. J. 


88,697 


April 


6, 1869. 


H. Danson, 


Baltimore, Md. 


123,979 


Feb. 


17, 1872 . 

• 






Reissue 






S. D. Castle, 


Bridgeport, Conn. 


6,252 


.Jan. 


26, 1875. J 






135,836 


Feb. 


11, 1873. 


C. P. Oliver, 


Newark, N. J. 


154,073 


Ang. 


11, 1874. 


C. P. Oliver, 


Newark, N. J. 


178,36] 


June 


6, 1876. 


W. Coupe, 


Soutb Attleborongh, Mass 


184,352 


Nov. 


14, 1876. 


J. N. DuSy, 


Newark, N. J. 


190,693 


May 


15, 1877. 


J. Sbarp, 


Cincinnati, 0. 


207,508 


Aug. 


27, 1878. 


H. N. Dodge, 


Brooklyn, N. Y. 


213,323 


Mar. 


18, 1879. 


Wm. Coupe, 


Attleborongh, Mass. 


215,640 


May 


20, 1879. 


J. H. Leddy, 


Newark, N. J. 


240,095 


Apri 


112, 1881. 


Wm. Coupe, 


South Attleborongh, Mass 


287,009 


Oct. 


23, 1883. 


L. Dederick, 


Newark, N. J. 



PAET VIIL 



CHAPTER XXXIX. 

TAKNIISTG PROCESSES. 

A LARGE number of processes have been invented for facili- 
tating the tanning of leather; but on account of various circum- 
stances there are only a few that are of value to the tanners of 
this country. 

Many of these processes have been patented by persons who 
are not practical tanners and who possess but a limited knowl- 
edge of the art in all its branches. 

A good tanner must be able to judge the result of his work 
under various conditions. 

It is often possible to save in the tanning of leather; but if 
care be not observed the loss in currying and finishing will 
greatly exceed the gain so made. The fact that a claimed im- 
provement in tanning methods may have been invented bv a 
person outside of the business should not, of course, weigh 
against it. MacBride was not a tanner, but to him we owe the 
discovery of the use of sulphuric acid for plumping hides, and 
the same might be said in relation to various other improve- 
ments. 

Ninety -nine one-hundredths of all the leather produced in 
the United States is tanned by one of three methods : First, 
by placing the hides or sides in vats of ordinary construction 
with a layer of ground bark between the hides or sides and 
supplying fresh ground bark and tan-liquor thereto at stated 
periods; second, by placing the hides, sides, and skins in vats 
and agitating them gently by appliances that do not injure 
either the fibre or grain; third, by sewing the skins into bags 



598 THE MAN'UFACTURE OF LEATHER. 

and forcing the tannin-liquor gently through the pores by 
pressure. 

In America the cheapness of hemlock and oak bark, bark 
extracts and native sumach, makes it quite unnecessary to so 
largely employ imported tanning materials, as is the case in 
many portions of Europe. 

All the above methods and materials for tanning leather have 
been enlarged upon in various portions of this work, and it now 
simply remains to give a synopsis of processes and materials not 
heretofore mentioned. 

Tanning Processes. 

A process consists of a series of acts performed in a definite 
and particular order in which each act or step co-operates with 
the other steps to produce a desired result. In tanning, these 
acts often consist in immersing the hide in different solutions. 
Where the substance of the invention consists in a single solu- 
tion only, the patents will be found under the head of "tanning 
materials." Where no bark or other tannin-containing sub- 
stance is used the patent will be found under " tawing," and 
where the novelty consists only in the apparatus or mechanical 
devices employed, look under the sub-class apparatus; for in- 
stance, if it is for facilitating the tanning process by agitating 
the hides and liquor in the vat, as by the England wheel, see 
list of patents for tan-vats, agitators, and handling appliances on 
page 358. 

Snyder punctures the grain or flesh sides of hides at any 
time before or after they go into the tan-vats in order to facili- 
tate the absorption of the tan-liquor, 

German employs any alkali, neutral salt, or other material 
that will cause fermentation of the bark so as fully to extract 
the tannin and allow it to enter into combination with the hide 
without becoming crystallized. 

Irving facilitates the absorption of the materials for liming 
and tanning hides by the application of electricity. 

HiBBARD, 1, depilates with lime and wood ashes ; 2, employs 
a composition of salt, sulphuric acid, sumach, oak bark, or any 
other tannin mixed together in water. Acetate of lead is used 



TANKING PROCESSES. 599 

in the compound employed for tanning white and thin leathers 
for gloves, linings, binders, etc. This process is also claimed to 
be applicable to tanning goat-skins, for Morocco. The ingre- 
dients employed and the proportions in which they are used in 
this process will be found on page 559. 

Fulton, after having bated the hides, 1, U:ses2 to 3 pounds of 
muriate of ammonia and 7 to 10 pounds of nitre dissolved in 
sufficient water to cover the pack of 20 slaughter hides ; 2, 
places the hides in weak bark-liquor for one day, or until a fine 
grain is formed ; 3, places hides in strong liquor for from three 
to five days, until sufficiently plumped ; 4, lays-away in bark 
and liquor. 

Enos, after the sole leather hides have been properly pre- 
pared, 1, steeps them in a solution composed of 40 pounds of 
Sicily sumach, or 150 pounds of underground native sumach, in 
250 gallons of water, to which are added 25 pounds of salt. 2. 
The hides after remaining in the first compound, kept at a tem- 
perature of about blood heat, have the liquor strengthened by 
200 gallons of strong oak or hemlock liquor and 15 pounds of 
salt, and the hides allowed to remain in the strengthened liquor 
for from twelve to twenty-four hours. 3. The hides are with- 
drawn from the above liquor and placed in the same quantity 
of strong, cold oak or hemlock liquor containing 20 pounds of 
salt in solution, and remain for five or six days. 4. The hides 
are removed from the cold liquor and placed in same quality 
and quantity of liquor, except that it is at about a temperature 
of about blood heat, and in which they remain for about five or 
six days. The last described operation is repeated for six or 
seven times, after which it is claimed that the sole leather will 
be tanned. While passing through the different stages the leather 
should of course be repeatedly handled. 

Keeler introduces oil into the tanning-liquor and facilitates 
its incorporation with the leather, agitating the liquor and leather 
with the England wheel shown in Fig. 112. 

Wattles. 1. Depilates with soap combined with salt and 
lime. 2. Combines soap with the tan-liquor. 

Gould. 1. Uses a combined solution of catechu and saltpetre. 
2. Employs a combined solution of catechu and alum. Other 



600 THE MANUFACTURE OF LEATHER. 

tannin containing materials may be employed in place of 
catechu. 

Hatch. 1. Bates the hides in the usual way until the lime 
is thoroughly worked out. 2. Einses in clean water. 3. Hangs 
up in a tight smoke-room, butt and neck, grain side out, and 
smokes in such a manner that the hides do not become heated, 
upper and collar leather being smoked six hours, other varieties 
according to the thickness of the hides. 4. Takes them out 
and soaks one hour in clean water. 5. Puts the hides in tan- 
ooze of moderate strength, and stirs and handles until the grain 
is evenly struck through. 6. Increases the strength of the 
liquor from day to day, and handles until the hides are tanned. 
To obtain a light color in the terra japonica or hemlock-ooze, 
adds a little sumach in the first handler in such proportions as | 
pound per side for upper leather. For heavy leathers, such as 
harness and sole leather, after being prepared in the usual way 
it is smoked six hours, then soaked in clear water one hour, then 
smoked again six hours, and soaked, and put into tan as above 
described. 

Daniels. For 20 cowhides : 1. Steeps them, after they 
have been properly prepared in the beam- house, for one day in 
15 pounds of catechu dissolved in sufficient water to cover the 
hides. 2. Takes out the hides and adds 15 pounds of catechu 
and 4 ounces of nitre or saltpetre, and in this liquor the hides 
are replaced and remain from three to five days according to 
thickness. 3. Prepares another liquor by dissolving 15 pounds of 
catechu in sufficient water to cover the hides and adds thereto 
IJ pounds sulphuric acid, which is thoroughly mixed, and in 
this they remain one day, when it is claimed that they will be 
tanned. In a later patent, Daniels combines the use of cream of 
tartar and bicarbonate of soda in making the liquor and using 
it for tanning. 

Kennedy makes a composition of 24 pounds of valonia or 
divi-divi, 8 pounds sulphate of soda, 4 pounds of sulphate of 
magnesia, or sulphate of potash, 1 pound of sulphate of alumina, 
2 pounds of sal-soda (carbonate of soda), 1 pound borax or 
boracic acid, the ingredients being dissolved separately in hot 
water or hot decoction of tan-bark, which is preferable. The 



TANNING PROCESSES. 601 

compound is then poured into a tank and thoroughly stirred 
to form the tanning-liquor, which may be drawn off as desired. 
The tanning-liquor thus formed is the most concentrated form, 
and on'ly suitable to be applied to hides in the advance stages of 
tanning, and must be largely diluted with water or bark-water 
before it is applied to hides at the commencement of the pro- 
cess, or else, before applying it to such hides, it should be partly 
spent by having had hides immersed in it that are in a more 
advanced state. 

The liquor is increased in strength as tanning progresses, 
the hides being handled frequently at first, but less handling 
will answer as the process advances. Hides intended for sole 
leather may, near the close of the process, be laid away with 
layers of ground bark, and then a liquid compound of 3 parts of 
the composition before mentioned, and 1 part of strong bark 
liquor poured over them until the hides are covered, and they 
remain undisturbed for twelve or fifteen days until tanned. 
Light skins are tanned by simply handling in the liquor. 

Noble. 100 calf-skins having been previously unhaired and 
bated, are: 1. Immersed in a preparation of 10 pounds of catechu 
dissolved in sufficient water to cover them, and kept in motion 
for two or three hours until well colored. 2. Then adds 10 
pounds more of catechu, and allows the skins to remain for 
fifteen to twenty-four hours, handling occasionally. 3. Removes 
the skins, and adds to the liquor in the vat 15 pounds of catechu, 
10 pounds of sulphate of soda, and 2 pounds common salt, 4. 
Immerses the skins in the liquor just prepared, and allows them 
to remain, with the addition of 10 pounds of catechu each day 
thereafter until tanned, which is usually from five to ten days. 
5. Removes from the previous liquor and prepares a new liquor 
termed the " fixing bath," consisting of water suflScient to cover 
the skins, to which are added 1 ounce of commercial nitric acid 
and I ounce of glycerine to every 4 gallons of water. In this 
mixture the skins are placed and handled frequently for from 
ten to eighteen hours, or until they assume a bright, suitable 
color, which may be varied by the time of immersion to suit 
the fancy. 6. Rinses the skins so as to insure the removal of 
free acid, when they are dried, and, it is claimed, ready for the 
currier. 



602 THE MANUFACTURE OF LEATHER. 

The skins during tlie wliole process are handled daily and 
freely exposed to the air. Heavy hides require more time, but 
the same relative proportion of the ingredients and order of their 
use is observed. 

Garge. After the hides have been unhaired and bated, to 
tan 100 sides of sole or harness leather : 

1. To 300 gallons of water adds 20 pounds sal-soda and 8 
pounds common salt. Immerses the sides in the above liquor 
for forty-eight hours. 

2. Places the sides in a liquor composed of 300 gallons of 
water, 60 pounds of catechu or terra japonica, and 8 pounds of 
common starch, and in this they remain for two days, the object 
being to set the grain. 

3. Puts them in a liquor composed of 300 gallons of water, 
80 pounds of terra japonica or catechu, 8 pounds of starch, and 
6 pounds of saltpetre, and in this liquor the sides remain until 
struck through. 

4. Places the sides in a liquor composed of 300 gallons water, 
80 pounds catechu, 8 pounds starch, and 10 pounds of alum ; the 
sides remain in this liquor for about six days, or till entirely filled 
and suflficientl}'' plumped to be solid and firm. 

Pag-e employs terra japonica or catechu, 3 parts; sulphate 
of alumina and potassa or alum, f part ; chloride of sodium, 
or common salt, 6 parts ; nitrate of potassa or saltpetre, 1 
part; sulphate of soda or Glauber's salts, 3 parts. These sev- 
eral ingredients are separately dissolved in hot water and thor- 
oughly mixed together in a vat. 

Water is then added in the proportion of 2| gallons to every 
pound of catechu when in a dry state. 

After being prepared in the usual way for tanning, the hides 
or skins are immersed in this liquor and allowed to remain 
therein for about forty-eight hours. The strength of the liquor 
is then increased until it bears the proportion of only 1| gallons 
of water to each pound of dry catechu, and in this the hides are 
kept froi;n eight to ten days, according to their relative size and 
thickness, in which time, it is claimed, they will be thoroughly 
tanned. 12 pounds of catechu and a proportionate quantity of 



TANNING PROCESSES. 603 

the otlier ingredients of this composition are sufficient to tan 
half a dozen calfskins, or an equivalent quantity of hides. 

EoBiNSON makes a terra japonica liquor, which we will call 
" No. 1," as follows: Puts 112 gallons of water in a suitable 
kettle heated over a fire, and adds 15 pounds of common terra 
japonica to it, and stirs until dissolved. Then adds 3 ounces of 
common sulphuric acid very cautiously, stirring the liquor 
rapidly. It is dangerous to pour strong sulphuric acid into hot 
water, therefore the sulphuric acid should be carefully poured 
in when the water is cold, or otherwise it should be greatly 
diluted. The acid precipitates the impurities contained in the 
catechu. 

The clear liquor is next racked off' from the cooling-tank 
into a vat (leaving the sediment behind), and is used as follows: 
For upper leather, add to the quantity of racked-off' liquor, No. 
1, described above, about ^ ounce of dissolved carbonate or 
calcined magnesia and about -^q ounce of sulphate of potassa, 
and then add as much water as will reduce liquor No. 1 to f its 
strength, which will be sufficient for 10 good-sized hides. The 
whole is now stirred up and forms the tanning-liquor No. 2, and 
the hides are placed in this liquor and are moved frequently for 
the first two days. 

Fresh clear liquor No. 1 must always be kept prepared to 
maintain the strength of the vat-liquor No. 2, in which the 
hides are being tanned. About 35 gallons of No. 1 liquor and 
1 ounce of sulphate of magnesia are added every second day at 
the early stage of the process, the hides being lifted out to put 
in the new liquor. 

The quantity of magnesia sulphate added to the liquor de- 
pends upon the amount of " plumping" which the hides require, 
which the practical tanner can judge by inspection. The No. 2 
liquor is gradually increased towards the end of the process. 
At the completion of the tanning process the hides are lifted 
out of the liquor and treated the same as when tanned by the 
ordinary process. 

About 100 skins or 50 calf-skins may be tanned in the same 
quantity of liquor as for the 10 hides above described. Harness 
and sole leather are made harder and more firm than upper leather; 
but the liquor for cow and ox-hides to produce them is made up 



604 THE MANUFACTUEE OF LEATHEE. 

exactly like ISTo. 2 described, and the process conducted in 
the same manner, with the exception that two ounces of sul- 
phate of potassa are employed or added to the first liquor which 
the hide receives. This salt, it is claimed, renders the sole 
leather hard and firm. The time required to tan harness leather 
is from four to eight weeks, and from six weeks to three months 
for sole leather. In making up new vats old liquors are used 
in place of water when they can be obtained. This method 
does not quicken the process of tanning, but it is claimed that 
the leather is made more flexible and durable than leather 
tanned by the ordinary process. 

Wyeth makes a soak of soft water, in which are dissolved 
1 pound of caustic potash and 2 pounds of sal-soda, which is 
kept at a temperature of about 100° F., and in this the dry 
hides are softened. Then breaks flesh in the usual way and 
works out thoroughly. Next hangs in a suitable sweat-room 
which is kept at a temperature of about 60° F., and in this 
apartment the skins remain until the hair comes off easily. They 
are then unhaired in the usual manner and afterwards subjected 
to a thorough rinsing in fresh, cold water, and then worked on 
the beam. 

The skins are next again suspended in the sweat-room, the 
temperature of which is still kept at about 60° F., and sub- 
jected to the steam or vapor which rises from the combustion 
of equal parts of wet spent tan-bark, damp horse-dung, and 
damp rotten wood ; this vaporizing process being employed in 
place of bating the skins, and also to facilitate the tanning. 

After being vaporized, the skins are again worked thoroughly 
and then subjected to a compound tan-liquor composed as fol- 
lows : Steep 510 pounds of hemlock or chestnut-oak bark, 50 
pounds of Sicily sumach, 25 pounds divi divi in a sufficient 
quantity of rain-water to receive 60 sides or 200 calf-skins. In 
this solution dissolve 5 pounds of alum. While the skins are 
in this liquor they must be handled frequently, and the strength 
of the first liquor kept up by the following compound : In a suf- 
ficient quantity of water dissolve 1 bale of japonica, 20 pounds 
Glauber's salts, and M pounds common salt, with which 



TANNING- PROCESSES. 605 

strengthen the first tanning-liquor from time to time as re- 
quired, handling the skins frequently till fully tanned. 

PiCKARD employs the essence of turpentine with sumach, 
catechu, or other vegetable or mineral coloring essence for tan- 
ning hides and skins. 

Wheelock first soaks the hides or skins in a liquor made 
of fermented corn-meal, one pound ; common salt, two pounds ; 
soft water, eight gallons. In this liquor the hides or skins 
remain until they are soft, and are then placed in the unhairing 
liquor, which is composed as follows : soft water, eight gallons ; 
carbonate of soda, one pound; lime, three pounds; leached lye, 
two quarts. In this liquor the hides or skins remain from two 
to four days, until the hair slips easily. Then the hair is re- 
moved and the hide put in a bating-liquor, which is made as 
follows : soft water, eight gallons ; nitric acid, one- fourth pound ; 
common salt, one pound. ; corn-meal, one-quart ; hen-manure, 
two quarts. In this liquor the hides or skins remain from two 
to four days, until they are reduced to their natural thickness. 

After the hides or skins have been removed from the bating- 
liquor place them in the tanning-liquor, which is made as follows : 
nitric acid, one pound; salts of ammonia, one-fourth pound; 
common salt, three pounds; fermented corn-meal, two quarts; 
catechu, three-fourths pound ; sumach, one pound. In this liquor 
the hides or skins remain for three days (more or less), and then 
remove them -into the second tanning-liquor, which is composed 
as follows : soft water, eight gallons ; fermented corn-meal, 
three quarts; nitric acid, one-half pound; salt of ammonia, 
one-eighth, pound ; common salt, two pounds; catechu, one 
pound ; sumach, one and one-half pound ; carbonate of soda, one- 
fourth pound. In this liquor the hides or skins remain for six 
days ; then they are washed and scoured with soft water, and 
after the water has been slicked out as much as possible the 
hides or skins are stuffed with the following compound : tallow, 
one pound; straits oil, one pint ; castor oil, one-half pint ; bees- 
wax, two ounces ; alcohol, one-fourth pint ; corn-starch, one- 
half pound ; to which may be added, for polish, white glue, two 
ounces, and sufficient lampblack to produce a good black. 



606 • THE MANUFACTURE OF LEATHER. 

The above quantities are sufficient for tanning one hide or 
four calf-skins. 

Kidder's method. To tan 12 hides of upper leather accord- 
ing to this method, use a sufficient quantity of water to cover 
the hides. Then dissolve 25 pounds of japonica or gambir. 
Then add the solution to the water. Then compound 3 quarts 
of the solution of potash or pearlash (the solution to equal the 
strength of strong lye) and 1 pound of sulphate of zinc. Dis- 
solve the zinc first in hot water. Then add the compound to 
the tanning-liquor. Then the liquor is ready for the hides. 
Place the hides in the tanning-liquor. Handle them up occa- 
sionally for two days. Then take them out and renew the 
liquor by adding 35 pounds of japonica or gambir, dissolved 
as before, and poured into the liquor. Then compound 3 quarts 
of the solution of potash or pearlash, 2 pounds of the sul- 
phate of zinc, 2 pounds of sulphur. Dissolve the sulphate of zinc 
and sulphur in boiling water before compounding with the 
alkaline. When compounded, add to the tanning-liquor. Then 
place the hides in the liquor. Handle them up for -i days ; then 
take them out and renew the liquor by adding 40 pounds of 
japonica or gambir, dissolved as before, two quarts of the solu- 
tion of pearlash or potash, 2 pounds of the sulphate of zinc, 
3 pounds of sulphur, IJ pound of sugar of lead, to be dissolved 
and compounded as before, then added to the tanning-liquor. 
Then place the hides in the liquor thus compounded, and 
handle them up occasionally for 5 days, which completes the 
tanning operation of the 12 hides. 

Calf-skins, harness, and all other kinds of leather should be 
treated in quantities of ingredients and time proportionally. 

To tan with bark, to each cord of bark use two gallons of the 
solution of potash or pearlash, 5 pounds of sulphate of zinc, 5 
pounds of sulphur, and 1| pound of sugar of lead. Before 
adding the above-named ingredients to the bark-liquor dissolve 
them in boiling water, then compound them and add them to 
the bark-liquor. For white-oak bark, double the quantities. 

Jenkins, for the purpose of liming the raw hides, say forty, 
takes 1 bushel of lime and 1 pound of potash, upon which he 
puts sufficient water to cover the hides by the liquor thus made. 



TANNIlSra PEOCESSES. 607 

In this solation they must remain for from two to three days 
according to circumstances, after which they are removed to 
undergo the bating process in a solution compounded of 1 peck 
of stone lime and 4 pounds of sulphur by boiling such ingre- 
dients in water, enough of the latter being added to make the 
desired quantity of liquor. After a period of one day or one 
day and a half the hides are taken out of the bating solution and 
transferred to the tanning-vat, which contains the tanning com- 
pounds. The latter is prepared from the following ingredients: 
Take 20 pounds terra japonica, 5 pounds of wood-acid, 5 
pounds of hops, 10 pounds of best sumach, to about 10 barrels 
of water, or enough of the latter to cover the hides. It is desir- 
able to subject the hides in the beginning of the tanning pro- 
cess to a solution somewhat weaker than the above will make. 
It is preferable to take only about two-thirds of the stated quan- 
tity of the ingredients above named to the required quantity of 
water, and add the remaining third as the operation progresses. 
After the hides have been in this liquor for about fifteen days, 
the tanning is claimed to be completed, and, after drying, the 
leather may be finished in any approved manner. 

Jluemelin's Tan Yat. 

In the process of tanning hides it is desirable to subject them 
to a weak liquor first, and gradually to increase the strength of 
the liquor until the process is completed. In practice, however, 
it is common to make the liquor of uniform strength, and apply 
it first at full strength to hides which have been so far advanced 
in the process as to require liquor of full strength. The liquor, 
in passing through one vat of hides, is reduced in strength 
thereby, w^hen it is of the required strength for the next pre- 
ceding vat. Ruemelin has therefore arranged the vats in a 
series as shown in Figs. 290 and 291, so that the liquor as it is 
reduced in strength will flow from the hides which are finished 
to those which have first been placed in the vats, so that by the 
time the liquor reaches the green hides, last introduced, it will 
become sufl&ciently reduced in strength as not to injure them. 
As the hides in the last vat are finished they are removed, and 
the hides in the next succeeding vat are moved forward into it, 



608 



THE MANUFACTURE OF LEATHER. 



and so on. All the hides in each vat are moved forward one 
vat at a time, from the first to the last vat in the series, every 
time a vat is emptied. Fig. 290 represents a vertical section, 
and 291 a top view of Eaemelin's tan vat. The hides are first 



Fig. 290. 




f 



II 




Fig. 291. 



K-- 



je: 



^ 



JT 



r 



.JC 



K 



G^ 



JI 



^ 



^^ 



J 



^ 



L^ 



r^ 



^ 



K 



J) 



JT 



C 



.J' 



K 



JB ^ 



Jl 



Li. 



K 



placed in vat J., and from thence moved forward to vats BCD 
E F G H I J. The liquid is first introduced into vat J", from 
whence it flows from one vat to another, as indicated by the 
arrows, until it reaches the vat J., the liquor being so reduced 
in strength b}^ the time it reaches such vat A that it is adapted, 
as stated, to the condition of the hides in their fresh state. 
Each vat in the series is provided with a pipe, K^ reaching from 
its bottom to near its top. The upper ends of the respective 
pipes project through a closely-fitting hole in the partition 
between the vats, thus forming a duct through which the liquor 
passes from one vat to another. As the mouths of the respec- 
tive pipes extend to near the bottom of the vats, it is obvious that 
the liquor will rise in the pipe as the vats are filled, and when 
the liquor reaches the level of the passage through the partition 
it will commence to flow from the bottom of one vat to the top 
of the next. The passages through the partitions are formed 
successively lower from the first, J", to the last, J., so that as the 
liquor is admitted into the first vat it will gradually find its way 
to the last, and will, as stated, be caused to pass in at the top 
and out at the bottom of the respective vats in the series. 



TANNING- PROCESSES. 



609 



List of all Patents for Processes for Tanning Leather, issued hy the 
Government of the United States of America, fi^om 1790 to 1883 
inclusive. 



No. 


Date 




Inventor. 


Residence. 


866 


Aug. 1, 


1838. 


A. Hickman and 
E. L. Davenport, 


Abingdon, Va. 


1,018 


Nov. 25 


1838. 


T. Chase, 


New York, N. Y. 


1,160 


May 30 


1839. 


W. Herapath, 


Bristol, Great Britain. 


1,741 


Aug. 25 


1840. 


A. H. Buzzell, 


Bridgetown, Me. 


2,332 


Nov. 10 


, 1841. 


S. Guilford, 


Lebanon, Pa. 


2,706 


July 8 


1842. 


A. Van Pelt, 


Bedminster, N. J. 


3,614 


July 5 


1844. 


J. Cox, 


Edinburgh, Great Britain. 


3,639 


July 24 


1844. 


Kettering and Vogle 


Hempfield, Pa. 


3,993 


April 10 


1845. 


S. Snyder, 


Dayton, 0. 


4,615 


July 2 


1846. 


W. Germar, 


Easton, Pa. 


5,261 


Aug. 28 


1847. 


Dr. A. TurnbuU, 


London, England. 


6,373 


April 24 


1849. 


E. Irving, 


New York, N. Y. 


6,790 


Oct. 16 


1849. 


H. Hibbard, 


Henrietta, N. Y. 


9,406 


Nov. 16 


1852. 


D. Kennedy, 


Reading, Pa. 


9,840 


July 12 


1853. 


J. J. Fulton, 


Monongahela City, Pa. 


11,325 


July IS 


1854. 


R. Enos, 


Woodstock, 111. 


12,148 


Jan. 2, 


1855. 


R. Keeler, 


Rochester, N. Y. 


13,443 


Aug. 14 


1855. 


0. B. Wattles, 


Waddington, N. Y. 


14,375 


Mar. 4 


1856. 


A. Steers, 


Medina, N. Y, 


14,399 


Mar. 11 


1856. 


R. Gould, 


Whitewater, Wis. 


15,157 


June 17 


, 1856. 


J. P. Williams, 


Salem, Mass. 


15,303 


July 8 


1856. 


S. W. Pingree, 


Methuen, Mass. 


15,736 


Sept. 16 


1856. 


G. W. Hatch, 


Princeton, 111. 


15,896 


Oct. 14 


, 1856. 


S. W. Pingree, 


Methuen, Mass. 


16,189 


Dec. 9 


1856. 


0. Rich, 


Cambridge, Mass. 


16,355 


Jan. 6 


1857. 


E. Daniels, 


Lafayette, Wis. 


17,043 


April 14 


1857. 


D. H. Kennedy, 


New Alexandria, Pa. 


17,868 


July 28 


1857. 


J. Carle, 


Kingston Township, Pa. 


18,030 


Aug. 18 


1857. 


L. L. A. Elie de La 
Peyrouse, 


Paris, France. 


19,201 


Jan. 26 


1858. 


B. G. Noble, 


Whitewater, Wis. 


19,756 


Mar. 30 


1858. 


C. Daniels, 


Elkhorn, Wis. 


20,502 


July 8 


1858. 


J. Morgan, 


Sumterville, S. C. 


20,565 


July 15 


1858. 


H. G. Johnson, 


Cleveland, 0. 


22,285 


Dec. 14 


1858. 


W. W. Garge, 


Rochester, N. Y. 


23,360 


Mar. 29 


1859. 


T. T. Fergusson, 


New York, N. Y. 


23,471 


April 5 


1859. 


H. Johnson, 


Farmersville, N. Y. 


24,278 


June 7 


1859. 


J. Brainerd and 
W. H. Burridge, 


Cleveland, 0. 


25,045 


Aug. 9 


1859. 


J. B. Read, 


Cold Spring, N. Y. 



39 



610 



THE MANUFACTURE OF LEATHER. 



No. 


] 


Date 




Inventor. 


Residence. 


25,241 


Aug. 


30, 


1859. 


J. Brainerd and 
W. H. Burridge, 


Cleveland, 0. 


25,315 


Sept. 


6, 


, 1859. 


J. Brainerd and 
W. H. Burridge, 


Cleveland, 0. 


25,522 


Sept. 


20, 


1859. 


T. S. Page, 


Milan, 0. 


25,671 


Oct. 


4, 


1859. 


S. Pierce and 
F. E. Beardsley, 


Castle Grove, la. 


26,966 


Jan. 


31, 


1860. 


W. D. Bunting, 


Cleveland, 0. 


27,088 , 


Feb. 


7, 


1860. 


P. Daniels, 


New York, N. Y. 


27,177 


Feb. 


14, 


1860. 


W. R. Webster, 


New York, N. Y. 


27,259 


Feb. 


21, 


1860. 


C. L. Robinson, 


Waukesha, Wis. 


27,338 


Mar. 


6, 


1860. 


D. Aldrich, 


St. Louis, Mo. 


27,823 


April 


10, 


1860. 


D. Needham, 


Oskaloosa, la. 


27,961 


April 24, 


1860. 


M. A. Bell, 


Rushford, N. Y. 


29,140 . 


July 


17, 


1860. 


D. J. Cochran, 


Centreville, Ind. 


80,220 


Oct. 


2, 


1860. 


R. Harper, 


Turnbull, 0. 


30,367 


Oct. 


9, 


1860. 


J. L. Wells, 


St. Louis, Mo. 


30,390 


Oct. 


16, 


1860. 


R. Crane, and W. 
Baldwin, 


Anamosa, la. 


30,392 


Oct. 


16, 


1860. 


A. Dietz, 


New York, N. Y. 


31,640 


Mar. 


5, 


1861. 


A. R. Wyette, 


West Middletown, Pa, 


32,526 


June 


11, 


1861. 


H. McKenzie, 


Talladega, Ala. 


33,183 


Sept. 


3, 


1861. 


J. Brainerd, 


Cleveland, 0. 


34,005 


Dec. 


24, 


1861. 


D. Mumma, 


Mt. Carroll, 111. 


34,192 


Jan. 


21, 


1862. 


M. Benas, 


New York, N. Y._ 


34,688 


Mar. 


18, 


1862. 


J. J. Johnson, 


Kalamazoo, Mich. 


36,636 


Oct. 


14, 


1862. 


Z. Baker, 


Erie, 111. 


42,619 


May 


3, 


1864. 


J. Burrill, 


Lynn, Mass. 


43,013 


June 


7, 


1864. 


W. Field and J. 
Townsend, 


Wilmington, Del. 


43,346 


June 28, 


1864. 


H. Stratton, Jr., 


Leavenworth, Kan. 


43,563 


July 


19, 


1864. 


J. S. Boothby, 


Portland, Me. 


48,740 


July 


11, 


1865. 


W. E. Terry, 


Wyoming, Wis. 


50,222 


Oct. 


3, 


1865. 


0. A. Coe, 


Charleston, S. C. 


50,936 


Nov. 


14, 


1865. 


J. J. Johnson, 


Kalamazoo, Mich. 


50,945 


Nov. 


14, 


1865. 


J. M. Muller, 


North Becket, Mass. 


51,762 


Dec. 


26, 


1865. 


W. H. Towers, 


New York, N. Y. 


52,464 


Feb. 


6, 


1866. 


B. F. Taber, 


New York, N. Y. 


52,655 


Feb. 


13, 


1866. 


B. Pickard,. 


Paris, France. 


53,688 


April 


[ 3, 


1866. 


J. Scliultz, 


Ellenville, N. Y. 


54,588 


May 


8, 


1866. 


M. W. Page, 


Franklin, N. H. 


56,643 


Oct. 


9, 


1866. 


Gr. W. Hernsey, 


G-reeubush, Wis. 


57,275 


Aug. 


21, 


1866. 


G. Aymard, 


New York, N. Y. 


57,409 


Aug. 


21, 


1866. 


W. H. Towles, 


New York, N. Y. 


57,795 


Sept. 


4, 


1866. 


J. N. Sturtevant and 
H. E. Jones, 


McGregor, la. 


59,109 


Oct. 


23, 


1866. 


G. D. Wheelock, 


Freedom, 0. 



TANNING PROCESSES. 



611 



mo. 


Date. 


Inventor. 


Residence. 


60,006 


Nov. 27, 1866. 


A. Hill, 


Dubuque, la. 


60,108 


Not. 27, 1866. 


J. Wood, 


Woodstock, Vt. 


60,472 


Dec. 18, 1866. 


J. W. Calef, 


Sudbury, N. H. 


60,701 


Jan. 1, 1867. 


J. Davis and 
J. McKelvy, 


Pawtucket, R. I. 


62,611 


Mar. 5, 1867. 


J. C. Coultou, 


Buffalo, N. Y. 


64,589 


May 7, 1867-. 




Jersey Shore, Pa. 


65,190 


May 28, 1867.- 


0. B. Evans, 


Buffalo, N. Y. 


65,323 


May 28, 1867: 


F. H. Wright, 


Richmond, Ind. 


68,631 


Sept. 10, 1867. 


G. L. Loverside, 


Burk Bank Gottages, En; 


69,042 


Sept. 17, 1867. 


r C. J. Gushing, 


St. Louis, Mo. 


69,636 


Oct. 8, 1867. 


} B. F. Walls, 
(w. A. Wood, 


> Hancock Gounty, Ky. 


70,337 


Oct. 29, 1867. 


A. W. Irish, 


Rochester, Minn. 


76,015 


Mar. 24, 1868. 


C. J. Weston, 


Gummington, Mass. 


76,824 


April 14, 1868. 


B. Schmidt, 


Hoboken, N. J. 


76,957 


April 21, 1868. 


D. Symonds, 




78,256 


May 26, 1868. 


F. J. Burcham, 


Racine, Wis. 


78,672 


June 9, 1868. 


E. Keith, 


Wabash, Ind. 


80,693 


Aug. 4, 1868. 


W. Windoes, 


Fond Du Lac, Wis. 


81,237 


Aug. 18, 1868. 


J. Wood, 


Woodstock, Vt. 


82,517 


Sept. 29, 1868. 


B. F. Gross, 


Trenton, Tenn. 


82,763 


Oct. 6, 1868. 


G. A. Starkweather, 


Waymart, Wis. 


83,433 . 


Oct. 27, 1868. 


G. Tippe, 


New York, N. Y. 


84,169 


Nov. 17, 1868. 


C. J. Burgh, 


Eau Claire, Wis. 


85,327 


Dec. 29, 1868. 


C. 0. Swani, 


Tolentino, Italy. 


87,325 


Mar. 2, 1869. 


J. F. Bechraann, 


Abbott's Corners, N. Y. 


87,894 


Mar. 16, 1869. 


C. A. Williams, Jr., 


Alba, Pa. 


88,764 


April 6, 1869. 


E. Lynch, 


Georgetown, D. G. 


91,504 


June 15, 1869. 


H. L. Wilcox, 


Percival, la. 


92,484 


July 13, 1869. 


C. Smith, 


Bell Air, 0. 


93,910 


Aug. 17, 1869. 


N. C. Russell, 


Gloversville, N. Y. 


98,916 


Jan. 18, 1870. 


W. B. Brittingham, 


La Fayette, Ind. 


100,520 


Mar. 8, 1870. 


A. D. Fullmer, 


Buffalo, N. Y. 


101,243 


Mar. 29, 1870. 


E. England, 


Mossy Creek, Tenn. 


104,276 


June 14, 1870. 


G. W. Crabtree and 
J. G. Stoakes, 


Ghocoville, Ark. 


104,734 


June 28, 1870. 


J. Henry, 


New York, N. Y. 


104,741 


June 28, 1870. 


J. Kidder, 


Urbana, 0. 


107,177 


Sept. 6, 1870. 


G. L. Jenkins, 


Omaha, Neb. 


109,714 


Nov. 29, 1870. 


W. B. Brittingham, 


La Fayette, Ind. 


110,562 


Dec. 27, 1870. 


W. H. Fuller, 


Brockport, N. Y. 


111,214 


Jan. 24, 1871. 


F. A. Holcomb and 
S. B. Jenks, 


Grand Rapids, Mich. 


111,583 


Feb. 7, 1871. 


W. G. Stone, 


Derby Lane, Vt. 



612 



THE MANUFACTURE OF LEATHER. 



No. 


Date. 


Inventor. 


Kesidence. 


112,285 


Feb. 28, 1871. 


A. Rock, 


New Orleans, La. 


114,596 


May 9, 1871. 


G. Pile, 


Blountsville, Tenn. 


116,578 


July 4, 1871. 


L. Falkeman, 


San Francisco, Cal. , 


118,089 


Aug. 15, 1871. 


D. Woodbury, 


Peabody, Mass. 


120,606 


Not. 7, 1871. 


R. P. Wilson, 


New York, N. Y. 


122,142 


Dec. 26, 1871. 


B. F. Wright, 


Winchester, Mass. . 


123,748 


Feb. 13, 1872. 


C. J. Tinnerholm, 


Quiucy, 111. 


125,020 


Mar. 26, 1872. 


^ J. Carter, 
t A. C. Keith, 


I Jersey City, N. J. 


127,947 


June 18, 1872. 


J. Bar ran, 


Cincinnati, 0. 


128,246 


June 25, 1872. 


J. Peters, 


St. James, Mo. 


128,938 


July 9, 1872. 


H. W. Southworth, 


Springfield, Mass. 


133,021 


Nov. 12, 1872. 


J. R. Enos, 


Peabody, Mass. 


133,140 


Nov. 19, 1872. 


S. Blanchard, Jr., 


Ashland, N. J. 


135,214 


Jan. 28, 1873. 


A. Fleischaner, 


Brooklyn, N. Y. 


136,082 


Feb. 18, 1873. 


W. Maynard, 


Salem, Mass. 


136,488 


Mar. 4, 1873. 


J.Carter and A.Keith, Jersey City, N. J. 


138,138 


April 22, 1873. 


J. Davis and J. 
Armstrong, 


Pittston, Pa. 


139,892 


June 17, 1873. 


C. Herveux, 


Islington, Eng. 


140,040 


June 17, 1873. 


J. B. Kite, 


Gyandotte, W. Va. 


141,459 


Aug. 5, 1873. 


( Gr. Rawle, 
( W. N. Evans, 


Bristol, Eng. 
Bedminster, Eng. 


144,500 


Nov. 11, 1873. 


R. Blake, 


Pontiac, 111. 


146,742 


Jan. 27, 1874. 


J. Anderson, 


Mount Pleasant, Pa. 


149,954 


April 21, 1874. 


H. Royer, 


San Francisco, Cal. 


150,405 


May 5, 1874. 


E. F. Dieterichs, 


Philadelphia, Pa. 






r L. M. Stockton, 
1 D. Stockton, and 
( W. A. Ward, 


> London, Canada. 


153,464 


July 28, 1874. 


153,636 

158,608 


July 28, 1874. 1 
Jan. 12, 1875. ) 


C. J. Tinnerholm, 


Keokuk, la. 


160,440 


Mar. 2, 1875. 


( H. Klemm, 
( C. Klemm, 


} Pfulliugen, Germany. 


160,902 


Mar. 16, 1875. 


R. Hart, 


Gloversville, N. Y. 


162,140 


April 20, 1875. 


G. A. Bartenbach 
and C. Richter, 


Detroit, Mich. 


163,191 


May 11, 1875. 


A. Haswell and 
J. C. Long, 


Webster City, la. 


164,792 


June 22, 1875. 


( E. A. Baldwin, 
( C. A. Holcombe, 


Phelps County, Neb. 
Lincoln, Neb. 


165,314 


July 6, 1875. 


A. D. Meritens, 


Paris, France. 


165,348 


July 6, 1875. 


E. Manasse, 


Napa, Cal. 


167,866 
169,076 


Sept. 21, 1875. 
Oct. 26, 1875. 


J. Angus, 
E. Bauer, 


Calais, Me. 
Williamsburgh, N. Y, 


169,102 


Oct. 26, 1875. 


R. Hart, 


Gloversville, N. Y. 



TANNING PROCESSES. 



613 



No. 


Date. 


Inventor. 


Residence. 


170,100 


Nov. 16, 1875. 


H. W. Mirrill and 
J. W. Hoitt, 


Lynn, Mass. 


170,623 


Nov. 30, 1875. 


H. Ely, 


Ballston Spa, N. Y. 


171,753 


Jan. 4, 1876. 


H. W. Adams, 


Philadelphia, Pa. 


174,761 


Mar. 14, 1876. 


J. Bent, 


Lowell, Mass. 


176,162 


April 18, 1876. 


W. E. Brock, 


Philadelphia, Pa. 


176,606 


April 25, 1876. 


J. L. de Montoison, 


Manchester, Eng. 


178,305 


June 6, 1876. 


A. C. Krueger, 


San Francisco, Cal. 


178,468 


June 6, 1876. 


C. Ricliter, 


Detroit, Mich. 


180,563 


Aug. 1, 1876. 


P. J. Dussand and 
J. Duchez, 


Bordeaux, France. 


180,947 


Aug. 8, 1876. 


J. A. J. Schultz, 


St. Louis, Mo. 


181,061 


Aug. 15, 1876. 


W. Farris, 


Yarmouth, Me. 


181,621 


Aug. 29, 1876. 


A. M. Barnes and 
W. F. Yocom, 


Weston, Mo. 


182,106 


Sept. 12, 1876. 


Wm. Coupe, 


South Attleborough, Mass 


182,198 


Sept. 12, 1876. 


J. J. Johnson, 


Columbus, 0. 


182,368 


Sept. 19, 1876. 


J. Kent, 


Glqversville, N. Y. 


182,684 


Sept. 26, 1876. 


H. Loescher, 


Chicago, 111. 


183,377 


Oct. 17, 1876. 


S. A. Darrach, 


Orange, N. J. 


184,114 


Nov. 7, 1876. 


M. J. Soderberg, 


Malmo, Sweden. 


185,799 


Dec. 26, 1876. 


P. Sweeney, 


New York, N. Y. 


187,492 


Feb. 20, 1877. 


J. A. J. Schultz, 


St. Louis, Mo. 


191,374 


May 29, 1877. 


H. Royer, 


San Francisco, Cal. 


196,672 


Oct. 30, 1877. 


J. Kent, 


Gloversville, N. Y. 


198,477 


Dec. 25, 1877. 


J. Wells, 


Wilmington, N. C. 


199,054 


Jan. 1, 1878. 


G. Goodwin, 


Cookshire, Quebec, Can. 


200,108 


Feb. 5, 1878. 


C. J. Tinnerholm, 


Brooklyn, N. Y. 


208,510 


Oct. 1, 1878. 


H. Breisacher, 


New York, N. Y. 


208,548 


Oct. 1, 1878. 


E. Tivet, 


Philadelphia, Pa. 


217,042 


July 1, 1879. 


E. W. Avery, 


Plymouth, N. H. 


221,187 


Nov. 4, 1879. 


G. Plumer and C. P. 
Kerans, 


Peabody, Mass. 


221,199 


Nov. 4, 1879. 


P. Turner and J. 
Turner, 


Chicago, 111. 


221,219 


Nov. 4, 1879. 


M. L. Doty, 


Winterset, la. 


223,200 


Dec. 30, 1879. 


J. Wells, 


Wilmington, N. C. 


229,928 


July 13, 1880. 


T. P. Tucker, 


Independence Co., Ark. 


230,225 


July 20, 1880. 


S. Bloom, 


San Francisco, Cal. 


230,841 


Aug. 3, 1880. 


S. Ullmo, 


Lyons, France. 


236,559 


Jan. 11, 1881. 


R. F. Dobson, 


Darlington, Wis. 


237,630 


Feb. 8, 1881. 


J. S. Swan, 


Mongaup Valley, N. Y. 


240,493 


April 19, 1881. 


G. D. Zonca, 


Venice, Italy. 


243,923 


July 5, 1881. 


R. Koenitzer, 


St. Louis, Mo. 


250,241 


Nov. 29, 1881. 


W. Harris, 


Forrest City, Me. 


254,962 


Mar. 14, 1882. 


J. W. Hammond, 


Osceola, Pa. 



614 



THE MANUFACTURE OF LEATHER. 



No. 


Date. 




Inventor. 


Eesidence. 


255,326 


Mar. 


21, 


1881. 


J. M. Oardway and 
Jas. Oardway, 


Boston, Mass. 


257,442 


May 


2, 


1882. 


J. Head, 


Hornellsville, N. Y, 


262,516 


Aug. 


8, 


1882. 


M. Turley, 


Council Bluffs, la. 


262,924 


Aug. 


22, 


1882. 


J. B. Bollman, 


Dayton, 0. 


271,804 


Feb. 


6, 


1883. 


J. F. Crawford, 


Oak Hill, Ala. 


289,588 


Dec. 


4, 


1883. 


A. J. Weeks and 
J. E. Weeks, 


Littleton, N. H. 



List of all Patents for Processes Employing 
Leather^ issued by the Government of the V 
from 1790 to 1883 inclusive. 



Apparatus for Tanning 
nited States of America, 



No. 


] 


Date 




Inventor. 


Kesidence. 




July 


9, 


1808. 


S. Parker, 






Oct. 
Dec. 


9, 
30, 


1812. ) 
1812. ) 


W. Edwards, 






Nov. 


4, 


1831. , 


A. Conwell, 






Dec. 


16, 


1833. 


Gr. H. Richards, 




1,079 


Feb. 


9, 


1839. 


W. Brown, 


Thompson, N. Y. 


1,160 


May 


30, 


1839. 


W. Herapath, 


Bristol, England. 


1,455 


Dec. 


31, 


1839. 


L. R. Palmer, 


Maryland, N. Y. 


1,906 


Dec. 


17, 


1840. 


W. Buchanan, 


Milford, Pa. 


2,868 


Dec. 


5, 


1842. 


D. H. Mason, 


Dahlonega, Ga. 


3,614 


June 


5, 


1844. 


J. Cox, 


Georgie Mills, Scotland, 


3,632 


June 15, 


1844. 


R. Downey, 


New Albany, Ind. 


3,688 


Aug. 


1, 


1844. 


W. Brown, 


Manchester, Md. 


4,253 


Nov. 


1, 


1845. 


F. D. Parmele, 


Akron, 0. 


5,165 


June 19, 


1847. 


L. C. England, 


New York, N. Y. 


7,089 


Feb. 


12, 


1850. 


W. H. Rosensteel, 


New Oxford, Pa. 


7,192 


Mar. 


19, 


1850. 


J. R. Innis, 


Easton, Pa. 


8,500 


Nov. 


4, 


1851. 


W. B. Milligan, 


Edinburg, Va. 


9,555 


Jan. 


25, 


1853. 


H. Britney, 


Springfield, 0. 


11,061 


June 


13, 


1854. 


N. Dodge, 


Oxford, N. H. 


14,375 


Mar. 


4, 


1856. 


A. Steers, 


Medina, N. Y. 


19,211 


Jan. 


26, 


1858. 


C. A. Shaw and 
J. Clark, 


Biddeford, Me. 


21,126 


Aug. 


10, 


1858. 


L. C. England, 


Owego, N. Y. 


.22,717 


Jan. 


25, 


1859. 


L. C. England, 


Owego, N. Y. 


23,360 


Mar. 


2a, 


1859. 


T. T. Fergusson, 


New York, N. Y. 


24,208 


May 


31, 


1859. 


J. Gore, 


Milford, N. H. 


24,457 


June 21, 


1859. 


J. Grore, 


Milford, Conn. 


24,560 


June 


28, 


1859. 


D. L. Hubbard, 


Glastenbury, Conn. 


24,727 


July 


12, 


1859. 


L. C. England, 


Owego, N. Y. 


25,045 


Aug. 


9, 


1859. 


J. B. Reed, 


Cold Spring, N. Y. 




TANNING PROCESSES. 



615 



No. 


Date 




Inveutor. 


Residence. 


29,656 


Aug. 21 


1860. 


D. Aldrich, 


St. Louis, Mo. 


30,062 


Sept. 18 


1860. 


W. H. Heald, 


Baltimore, Md. 


33,448 


Oct. 8, 


1861. 


S. J. Patterson, 


Bridgeport, Conn. 


34,815 


April 1, 


1862. 


W. Bush, 


Wilmington, Del. 


40,575 


Nov. 10 


, 1863. 


V. E. Rusco, 


Chicago, 111. 


43,013 


June 7 


1864. 


W. Fields and 
J. Towusend, 


Wilmington, Del. 


43,258 


June 21 


1864. 


H. Leibermann, 


Paducah, Ky. 


43,787 


Aug. 9 


1864. 


J. Mauren, 


Marseilles, France. 


47,844 ^ 

Reissue > 

2,519) 


May 23 


1865. 


B. H. McNulty and 


Philadelphia, Pa. 


Mar. 19 


1867. 


W. Kern, 


Mansfield, 0. 


48,361 


June 27 


1865. 


0. H. Brewer, 


Shannon, 111. 


50,228 


Oct. 3, 


1865. 


C. R. Dean, 


Randolph, N. Y. 


50,998 


Nov-. 21 


1865. 


H. W. Adams, 


Irvington, N. J. 


51,655 


Dec. 19 


1865. 


H. Leibermann, 


Paducah, Ky. 


51,870 


Jan. 2 


1866. 


T. Sharp, 


Nashville, Tenn. 


55,333 


June 5 


1866. 


M. H. Merriam and 
E. L. Norton, 


Charlestown, Mass. 


57,275 


Aug. 21 


1866. 


G. Aymard, 


New York, N. Y. 


59,157 


Oct. 30 


1866. 




Bromfield, Me. 


59,469 


Nov. 6 


, 1866. 


J. Snell, ,Tr., 


Patterville, Pa. 


60,524 


Dec. 18 


1866. 


J. J. Johnson, 


Allegheny City, Pa. 


63,869 


Aprill6 


1867. 


C. J. Dumery, 


Paris, France. 


68,861 


Sept. 17 


1867. 


L. C. England, 


Owego, N, Y. 


75,391 


Mar. 10 


1868. 


C. Doty, 




76,134 


Mar. 31 


1868. 


H. W. Adams, 


Irvington, N. J. 


76,777 


April 14, 


1868. 


L. L. Kelly, 


Delaware Station, Ind 


76,784 


April 14 


1868. 


J. W. Lull, 


Glen Hope, Pa. 


76,957 


April 21 


1868. 


D. Symonds, 


Marlow, N. H. 


80,981 


Aug. 11 


1868. 


H. Lucas, 


Rousburgh, 0. 


82,815 


Oct. 6 


1868. 


A. G. Eaton, 


Gouverneur, N. Y. 


84,190 


Nov. 17 


1868. 


S. Hosmer, 


Concord, Mass. 


88,764 


April 6 


1869. 


E. Lynch, 


Georgetown, D. C. 


92,615 


July 13 


1869. 


J. E. Kanffelt, 


Shrewsbury, Pa. 


92,776 


July 20 


1869. 


0. W. Bean, 


Farmington, Tex. 


101,213 


Mar. 29, 


1870. 


0. W. Bean and 
W. B. Rowland, 


Tecumseh, Mich. 


101,661 


April 5 


1870. 


L. T. Robinson, 


New York, N. Y. 


101,812 


Aug. 12 


1870. 




Wilmington, Del. 


105,169 


July 12 


1870. 


J. Champion, 
r J. Robijison, 


Woburn Centre, Mass. 


106,209 


Aug. 9 


1870. 


} S. F. Robinson, 
(c. C. Putnam, 


> Skowhegan, Me. 


112,285 


Feb. 28 


1871. 


A. Rock, 


New Orleans, La. 


112,332 


Feb. 28 


1871. 


L. C. England, 


Philadelphia, Pa. 



61-6 



THE MANUFACTURE OF LEATHER. 



Wo. 




Date, 




118,034 


Aug. 


15, 


1871. 


119,238 


Sept. 


26, 


1871. 


119,822 


Oct. 


10, 


1871. 


123,105 


Jan. 


30, 


1872. 


139,892 


June 


n, 


1873. 


158,438 


Jan. 


.% 


1875. 


159,510 


Feb. 


9, 


1875. 


180,563 


Aug. 


1, 


1876. 


218,539 


Aug. 


12, 


1879. 


23(5,659 


Nov. 


23, 


1880. 


242,954 


June 


14, 


1881. 


245,142 


Aug. 


2, 


1881. 


266,174 


Oct. 


17, 


1882. 


274,336 


Mar. 


20, 


1883. 


278,331 


May 


29, 


1883. 


278,981 


June 


5, 


1883. 


290,885 


Dec. 


25, 


1883. 



Inventor. 

W. Masek, 

W. Morris, 
I W. Coburn, 
* F. Winslow, 

K. M. Jarvis, 

C. Harveux, 

H. Reed, 

C. Haserick, 

P. J. Dussand and 
J. Duchez, 

G. King, 

J. Davis, 

C. Michel, Jr., 
' C. Kollen, 

. G. Hertzog, 
J. Davis, 
W. Masek, 
B. D. Hyam, 

D. Halsey, Jr., 

E. R. Locke, 
B. D, Hyam, 



Residence. 
Nashville, Ky. 
Philadelphia, Pa. 
East Walpole, Mass. 
South Dedham, Mass. 
Peabody, Mass. 
Islington, England. 
Atlanta, Gra. 
Maynard, Mass. 
Bordeaux, France. 

Washington, D. C. 
Allegheny, Pa. 

1- Reims, France. 

Allegheny, Pa. 
Philadelphia, Pa. 
Washington, D. C. 
Newark, N. J. 
Keene, N. H. 
Washington, D. C. 



List of all Compounds and Materials for Tanning and also for Taw- 
ing Leather and for Preparing Raw Hides, that are especially 
claimed or mentioned in any Patent, issued hy the Government of the 
United States of America, from 1790 to 1883 inclusive. 



No. 


Date 




Inventor. 


Kesidence. 


836 


July 12, 


1838. 


A. A. Hayes, 


Roxbury, Mass. 


4,007 


April 22, 


1845. 


G. C. Close and 
E. Field, 


Port Chester, N. Y. 


9,181 


Aug. 10, 


1852. 


A. K. Eaton, 


Rochester, N. Y. 


9,406 


Nov. 16, 


18.52. 


D. Kennedy, 


Reading, Pa. 


12,102 


Dec. 19, 


1854. 


G. Reynolds, 


Bangor, Me. 


12,139 


Jan. 2, 


1855. 


0. Rich, 


Cambridge, Mass. 


13,443 


Aug. 14, 


1855. 


0. B. Wattles, 


Waddingtou, N. Y. 


15,157 


June 17, 


1856. 


J. P. Williams, 


Salem, Mass. 


17,043 


April 14, 


1857. 


D. H. Kennedy, 


New Alexandria, Pa. 


17,867 


July 28, 


1857. 


J. Carle, . 


Kingston Township, Pa, 


18,030 


Aug. 18, 


1857. 


L. L. A. Elie de la 
Peyrouse, 


Paris, France. 


19,756 


Mar. 30, 


1858. 


C. Daniels, 


Elkhorn, Wis. 


21,755 


Oct. 12, 


1858. 


B. Harrington and 
N. Russell, 


China, Me. 


23,471 


April 5, 


1859. 


H. Johnson, 


Farmersville, N. Y. 


25,241 


Aug. 30, 


1859. 


J. Brainard and 
W. H. Burridge, 


Cleveland, 0. 



TANNING PROCESSES. 



617 



No. 


Date 




Inventor. 


Residence. 


25,522 


Sept. 20, 


1859. 


T. S. Page, 


Milan, 0. 


26,800 


Jan. 10, 


1860. 


R. B. Thompson, 


Gailesburg, HI. 


27,088 


Feb. 7, 


1860. 


P. Daniels, 


Le Roy, N. Y. 


27,648 


Mar. 27, 


1860. 


J. Unessley, 


Gowanda, N. Y. 


27,859 
29.143 


April 10, 
July 17, 


1860. i 


J. Connell, 


Port Huron, Mich. 


29,488 


Aug. 7, 


1860. 


A. Hill, 


Dubuque, la. 


30,220 


Oct. 2, 


1860. 


R. Harper, 


Trumbull, 0. 


30,367 


Oct. 9, 


1860. 


J. L. Wells, 


St. Louis, Mo. 


30,390 


Oct. 16, 


1860. 


R. Crane and W. 
Baldwin, 


Anamosa, la. 


30,392 


Oct. 16, 


1860. 


A. Dietz, 


New York, N. Y. 


32,526 


June 11, 


1861. 


H. McKenzie, 


Talladega, 111. 


33,314^ 










Reissue > 


Sept. 17, 


1861. 


P. W. Thomas, 


Levee, Ky. 


2,310 J 










33,388 -^ 










Reissue > 


Oct. 1, 


1861. 


G. W. Hatch, 


Princeton, 111. 


2,384) 










33,564 ^ 










Reissue > 


Oct. 29, 


1861. 


W. Beach, 


Hamden, Conn. 


2,560 5 










33,790 


Nov. 26, 


1861. 


J. M. Muller, 


Richmondville, N. Y, 


34,609 


Mar. 4, 


1862. 


.J. Brainerd, 


Cleveland, 0. 


38,525 


May 12, 


1863. 


H. C. Williams, 


Lancaster, Pa. 


41,666 


Feb. 16, 


1864. 


J. Wonder, 


Trucksville, Pa. 


43,188 


June 21, 


1864. 


S. Dunseith, 


Philadelphia, Pa. 


44,234 


Sept. 13, 


1864. 


J. W. Taylor, 


North Collins, N. Y. 


46,443 


Feb. 21, 


1865. 


G. Bottero, 


Boston, Mass. 


46,646 


Feb. 21, 


1865. 


C. Burton, 


Union, Me. 


49,886 


Sept. 12, 


1865. 


E. Keith and B. Thorn 


, La Fontaine, Ind. 


50,662 


Oct. 24, 


1865. 


J. Price, 


Edgefield District, S. 


50,872 


Nov. 7, 


1865. 


S. A. Hickel, 


Roan Co., W. Va. 


51,407 


Dec. 5, 


1865. 


J. E. Park, 


Seguin, Texas. 


53,688 


April 3, 


1866. 


J. Schultz, 


Ellenville, N. Y. 


57,409 


Aug. 21, 


1866. 


W. H. Towers, 


New York, N. Y. 


57,795 


Sept. 4, 


1866. 


J. N. Stui-tevant and 
H. E. Jones, 


McGregor, la. 


59,251 


Oct. 30, 


1866. 


H. Napier, 


Elizabeth, N. J. 


60,472 


Dec. IS, 


1866. 


J. W. Calef, 


Salisbury, N. H. 


60,548 
60,549 


Dec. 18, 
Dec. 18, 


1866. 1 
1866. ) 


J. A. Pease, 


New York, N. Y. 


60,701 


Jan. 1, 


1867. 


J. Davis and 
J. McKelvey, 


Pawtucket, R.J. 


65,323 


May 28, 


1867. 


F. H. Wright, 


Richmond, Ind. 


65,934 


June 18, 


1867. 


W. H. Newby, 


Seymour, Ind. 



618 



THE MANUFACTURE OF LEATHEE. 



No. 

66,432 
67,563 


Date 
July 2, 
Aug. 6, 


1867. 
1867. 


Inventor. 
J. Campbell, 
J. Melian, 


Residence. 
Leona, Pa. 
Newark, N. J. 




68,335 
68,511 


Sept. 
Sept. 


3, 
3, 


1867. 
1867. 


A. Appleby, 
W. Johnson, 


Bi-ownfield, Me. 
Shirleysburg, Pa. 




68,631 


Sept. 


10, 


1867. 


G. L. Loversidge, 
rC. J. Cashing, 
]b. F. Walls, and 
tw. A.Wood, 


Burry Bank Cottages 


Eng 


69,636 


Oct. 


8, 


1867. 


>- Hancock Co., Ky. 




71,293 


Nov, 


26, 


1867. 


C. Frank, 


Cincinnati, 0. 




75,535 


Mar. 


17, 


1868. 


J. Diehl, 


East Freedom, Pa. 




75,794 


Mar. 


24, 


1868. 


L. S. Robbing, 


New York, N. Y. 




76,957 
77,099 


April 21. 
April 21, 


1868. 
1868. 


D. Symonds, 
L. F. Robertson, 


Marlow, N. H. 
West Farms, N. Y. 




78,672 


June 


9, 


1868. 


( E. Keith and 
\a. A. Eylar, 


Wabash, Ind. 
Pontiac, HI. 




80,693 


Aug. 


4, 


1868. 


W. Windoes, 


Fond du Lac, Wis. 




81,237 


Aug. 


8, 


1868. 


J. Wood, 


Woodstock, Vt. 




81,587 
82,517 


Sept. 
Sept. 


1, 

29, 


1868. 
1868. 


Gr. Bossiere, 
B. F. Gross, 


Paris, France. 
Trenton, Tenn. 




83,073 


Oct. 


13, 


1868. 


S. Lusten, 


Linesville, Pa. 




84,169 


Nov. 


17, 


1868. 


C. J. Bugh, 


Eau Claire, Wis. 




84,734 


Dec. 


8, 


1868. 


N. Cox, 


Salem, 111. 




86,808 


Feb. 


9, 


1869. 


J. P. Bridge, 


Boston, Mass. 




91,504 


June 


15, 


1869. 


H. L. Wilcox, 


Percival, la. 




93,498 


Aug. 


10, 


1869. 


N. A. Thornton, 


Conikee, Ala. 




94,805 


Sept. 


14, 


1869. 


J. Wood, 


Woodstock, Vt. 




98,884 


Jan. 


18, 


1870. 


F. P. Porcher, 


Charleston, S. C. 




104,276 


June 


14, 


1870. 


G. W. Crabtree and 
G. Stoakes, 


Chocoville, Ark. 




107,713 


Sept. 


27, 


1870. 


C. F. Panknin, 


Charleston, S. C. 




109,714 
110,562 
111,562 


Nov. 
Dec. 
Feb. 


?9, 

27, 
7, 


1870. 
1870. 
1871. 


W. B. Brittingham, 
W. H. Fuller, 
W. Parks, 


La Fayette, Ind. 
Brockport, N. Y. 
Meadville, Pa. 




112,285 


Feb. 


28, 


1871. 


A. Rock, 


New Orleans, La. 




114,941 
115,100 


May 
May 


16, 
21, 


1871. 
1871. 


A. Hisey, 

F. P. Porcher, 


Tama City, la. 
Charleston, S. C. 




117,241 


July 


25, 


1871. 


A. T. Atherton, 


Lowell, Mass. 




123,118 


Jan. 


30, 


1872. 


J. M. MuUer, 


Cobbleskill, N. Y. 




125,020 


Mar. 


26, 


1872. 


J. Carter and 
A. C. Keith, 


Jersey City, N. J. 




128,938 


July 


9, 


1872. 


H. W. Southworth, 


Springfield, Mass. 




132,269 


Oct. 


15, 


1872. 


W. Farris, 


Yarmouth, Me. 




140,040 
143,105 
144,500 


June 
Sept. 
Nov. 


17, 
23, 
11, 


1873. 
1873. 
1873. 


J. B. Heite, 
W. Thilmany, 
R. Blake, 


Guyandotte, W. Va. 
Cleveland, 0. 
Pontiac, 111. 




146,742 


Jan. 


27, 


1874. 


J. Anderson, 


Mt. Pleasant, Pa. 





TANNING PEOCESSES. 



619 



No. 




Date. 


Inventor. 


Residence. 


148,056 


Mar. 


3, 1874. 


G". W. Hatch, 
/ T. M. Stockton, 
< D. Stockton, and 
(w. A. Ward, 


Lawrence, Kan. 
> London, Can. 


153,464 


July 


28, 1874. 








159,366 


Feb. 


2, 1875. 


W. R. Stace, 


Rochester, N. Y. 


163,191 


May 


11, 1875. 


A. Haswell and 
J. C. Long, 


Webster City, la. 


164,792 


.June 


22, 1875. 


E. A. Baldwin and 
C. A. Halcombe, 


Phelps Co., Neb. 
Lincoln, Neb. 


165,348 


July 


6, 1875. 


E. Manasse, 


Napa, Cal. 


165,731 


July 


20, 1875. 


G. Herrick, 


Kilbourn City, Wis. 


165,822 


July 


20, 1875. 


G. W. Hatch, 


Lawrence, Kan. 


169,076 


Oct. 


26, 1875. 


E. Bauer, 


Williamsburg, N. Y. . 


174,110 


Feb. 


29, 1876. 


E. Bradley, 


St. Leonard, Can. 


176,162 


April 18, 1876. 


W. E. Brock, 


Philadelphia, Pa. 


178,919 


June 


20, 1876. 


J. Foley, 


Montreal, Can. 


182,368 


Sept. 


19, 1876. 


J. Kent, 


Gloversville, N. Y. 


185,799 


Dec. 


26, 1876. 


P. Sweeney, 


New York, N. Y. 


193,520 1 
193,521) 


July 


24, 1877. 


F. Knapp, 


Brunswick, Germany, 


196,081 


Oct. 


]6, 1877. 


F. Funke, 
^ G. De Cordova, 
) M. Wise, 
( H. D. Darrell, 


Detroit, Mich. 
/ Brooklyn, N. Y. 


196,339 


Oct. 


23, 1877. 


} New York, N. Y. 








(Brooklyn, N. Y. 


198,478 


Dec. 


25, 1877. 


J. Wells, 


Wilmington, N. C. 


200,108 


Feb. 


5, 1878. 


C. J. Tinnerholm, 


Brooklyn, N. Y. 


230,841 


Aug. 


3, 1880. 


S. Ullmo, 


Lyons, France. 


231,035 


Aug. 


10, 1880. 


P. Gondolo, 


Paris, France. 


231,489 


Aug. 


24, 1880. 


J. Holtz, 


Berlin, Prussia, Germany, 


235,923 


Dec. 


28, 1880. 


H. L. Wilcox, 


Lincoln, Neb. 


236,115 


Dec. 


28, 1880. ) 
4, 1881. ) 


H. Trenk, 


Berlin, Germany. 


236,280 


Jan. 






237,007 


Jan. 


25, 1881. 


J. Foley, 


Montreal, Can. 


260,322 


June 


27, 1882. 


C. Richter, 


St. Paul, Minn. 


262,766 


Aug. 


15, 1882. 


C. T. Hayden, 


Whitesborough, Tex. 


271,804 


Feb. 


6, 1883. 


J. F. Crawford, 
^ E. Logue, 


Oak Hill, Ala. 


283,798 


Aug. 


28, 1883. 


} M. T. Jones, and 
(c. E. MorriU, 


> Deering, Me. 


286,491 


Oct. 


9, 1883. 


•T. Shaw, 


Hindmarsh, S. Australia. 


287,255 


Oct. 


23, 1883. 


F. E. Dietsch, 


Woodbury Falls, N. Y. 



620 THE MANUFACTURE OF LEATHER. 



CHAPTEE XL. 

TANNING AND COLORING HIDES AND SKINS WITH THE HAIR 
AND FUR ON. 

PiNGEE obtained two patents for tanning hides with the hair 
on, the first being for the process of shaving off" after the hide 
has been fleshed, the inner layer of the skin, or the same and a 
part of the coriura preparatory to immersing the hide in the 
liquors. The second patent relates to the preparation and use 
of the tanning liquors. 

1. For 25 hides use 5 hogsheads of water, 1 peck lime, 5 
pounds sal-soda, and 12 pounds soda-ash ; or, instead of the sal- 
soda and soda-ash, 15 pounds of soda-ash may be used. The 
hides remain in this solution for twelve or more hours ; but 
not long enough to start the hair. 

2. Kinses in cold water. 

3. Steeps in a solution composed of 5 hogsheads of water, 1 
bushel of muriate of soda, and 12 pounds of sulphuric acid. In 
this solution they remain twenty-four hours or more, according 
to the thickness of the hide, and are frequently stirred. 

4. Immerses in a solution composed of 5 hogsheads of water 
and 50 pounds Bombay catechu. 

5. Steeps the hides in strong bark-liquor, in which they 
remain ten or twelve days. 

6. Adds to the bark-liquor 50 pounds sumach and 25 pounds 
ground alum, and suffers the hides to remain one week longer 
in such solution ; but stirs them occasionally in the mean time, 
and the process is completed. 

Johnson. For tanning light skins with the hair on them — 
such as sheep, fox, coon, or minx-skins, etc. — 1. Soaks, fleshes, 
and cleans in the usual manner. 2. Makes a solution in the 
following proportions : to | bushel wheat-bran add 6 gallons of 
soft, hot water, and let it stand in a warm room, and agitate 
until it ferments. Then strain out the liquor and dissolve 



TANNING AND COLORING WITH THE HAIR ON. 621 

therein 4 pounds of chloride of sodium or common salt, and 
then add 1| pounds sulphuric acid while agitating the liquor. 
This liquor acts as a mordant for settling a variety of colors, 
which are cheap and more durable than if made in the usual 
manner of sponging colors after tanning. 3. Light hides re- 
quire to be handled in the above liquor for one to three hours. 
4. Rinse and hang out to dry in the shade. 6. Stuff', when 
nearly dry, with a compound of f fish oil, ^ alcohol ; to which 
add flour paste and melted tallow equal parts in order to thicken. 
To make this compound water-proof and India-rubber or bees- 
wax. 6. Dry the skins. 

CoE. 1. Soaks the light hide or skin with the wool, hair, or 
fur on. 2. Fleshes in the usual manner. 3. Makes a solution 
composed of 8 gallons soft water ; 1 quart potatoes, boiled and 
mashed ; 8 quarts rye or oat bran ; 5 pounds common salt : | 
pound oxalic acid. Stirs the potatoes and bran together with 
the water in the proportion above specified, and lets it 
stand in a warm room until it ferments. Then adds the salt, 
stirring until it is dissolved, and finally under continuous 
agitation adds the oxalic acid. This solution, which is termed 
the "first solution," imparts no color to the leather or fur. 
4. For heavy hides or skins, such as calf-skins or cowhides, adds 
to the above solution a liquid made of the buds of sumach, 
melted catechu, and zinc mixed together in about the following 
proportions: 1 quart extract of the butts of sumach, 3 pounds 
melted catechu or Sicily sumach, ^ pound kino or cranes bill. 
It is claimed that this solution plumps and gives the leather a 
body. Light hides require to be handled from thirty minutes 
to one hour ; they are then rinsed in soft, warm water, and hung 
out in the shade to dry. 5. When the hides or skins are nearly 
dry they are stuffed with oil, tallow, and flour paste, and then 
hung in the air to dry. 

Carter and Keith's process is adapted for tanning hides and 
skins with the hair on, and for dressing furs. 

In carrying this invention into practice, prepare a solution 
composed of the following ingredients in substantially the pro- 
portions named : Carbonate of soda, three pounds ; nitrate of 
potash, three ounces ; chloride of sodium, three ounces ; prus- 



622 THE MANUFACTURE OF LEATHER. 

siate of potash, three ounces; acetate of lead, three ounces; 
green vitriol, three ounces ; soft water, nine gallons. In place 
of the carbonate of soda, three gallons of common lye may be 
used, if preferred. Pulverize the ingredients and dissolve them 
in the water while hot. The skins to be tanned must be fleshed 
in the usual manner, whether green or dry. If dry, they must 
be soaked in water until softened. They are then immersed in 
the above solution, which is kept at a lukewarm temperature, 
and are handled or agitated to expose all parts equally to the 
action of the liquid. The time which they are required to re- 
main in the solution to become tanned varies with the kind and 
thickness of the skin from thirty minutes to two hours. After 
having been in the solution a sufl&cient time they are taken out, 
when it will be found that the hair or wool is loosened and the 
grain raised, so that they should be handled with care and im- 
mediately on removal from the solution rinsed in cold water, 
which will reset the hair and prevent depilation, and after being 
rinsed they are hung up in the shade to dry. 

The skins having been tanned and dried, must now be treated 
with the following composition : Soft soap, one gallon ; fish oil, 
one quart ; borax, one ounce ; chloride of soda, four ounces ; 
alcohol, four ounces ; all of which ingredients are thoroughly 
mixed in two quarts of hot soft water. The dried skins which 
are dressed with the hair, wool, or fur on must be washed with 
the composition on the flesh side only, and this repeated as 
many times as necessary to render them somewhat soft, and in 
a condition to be worked soft by rubbing or beating. The tan- 
ning-liquid does not affect the hand injuriously, and acts as a 
disinfectant of any fetid or oft'ensive odor that appertains to the 
skins, whereby the natural oil and impurities of wool are decom- 
posed and furs are cleansed and rendered fit for wear ; the treat- 
ment also serving as a preventive against the attacks of moth. 

Tanning and Coloring Beaver^ Otter^ and any other Shins with 
the Hair or Fur on. 

Bugh''s Method for Tanning Beaver^ Otter^ or any other Sldns^ 
loith the Hair or Fur on. — The skins according to this method 
should be soaked (if dry) from 12 to 16 hours, then thoroughly 
fleshed, then returned to the soak for from 6 to 8 hours lonsrer. 




TANNING AND COLOKING WITH THE HAIE ON. 623 



They should then be washed as follows : — 

Take sufficient warm, soft water to wash them, to which add 
sal-soda until the water feels slippery, then wash thoroughly ; 
next wash them well in warm, strong soapsuds, then rinse 
well through 2 or 3 waters, and wring out as dry as possible. 
The skins are then ready for the tan-liquor, which is prepared 
as follows : — 

2 gallons cold, soft water. 

2 pounds Glauber's salts. 

1 pound alum. 

1 pound common salt. 

J an ounce sulphate of zinc. 

Melt 1 pound terra japonica in J gallon of the above prepara- 
tion, over a slow fire, then mix all together. 

All the ingredients should be pulverized, as they will dissolve 
much more quickly. 

Place the skins in the tan, and handle by pulling and stretch- 
ing thoroughly, then let remain 2 or 3 days ; if heavy furs, 
such as bear-skins, 4 or 5 days. 

Then rinse in 3 or 4 clean waters, wring out as dry as possible, 
and hang in the shade to dry. When nearly dry, work them 
occasionally by stretching, etc., or on the beam with the fleshing- 
knife. When dry, finish up on the beam, by working the 
middle or thick part of the skin down, until it is even, or as 
thin as the edges or flanks. 

A currying- knife, with a fine edge, is the best tool to do this 
with, or it may be done with coarse sand-paper, rolled on a round 
stick, using it the same as a knife. 

If it is desired to pluck the hides, after washing them through 
the alkali, and rinsing, lay them in clean, cold water for a day 
or two longer, or until the " guard-hairs" pull out without 
breaking. 

Care must be taken not to let the skin taint. If it does, it 
will loosen the fur, as the fur is only on the grain while the 
" guard-hairs" go through into the pelt. 

Muskrats have very tender skins, which should be treated 
somewhat differently from heavier furs. 

Soak in clean, cold water for 10 or 12 hours, or until all hard 



624: THE MANUFACTURE OF LEATHER. 

spots are softened ; then flesh as well as possible ; then wash as 
directed to wash furs ; then put them in the tan-liquor for furs ; 
handle the same as other furs, and let remain for two or three 
hours ; then wring out, and flesh again, and return to tan-liquor 
for two or three hours longer; then wring and rinse, and finish 
up as directed for finishing furs. If the skins are well fleshed 
the first time, a second fleshing is not necessary. 

A rich, nice gloss will be formed on all furs, if tanned and 
finished as described. 

To Color Furs. 

After soaking soft, wash in a middling-strong sal-soda water, 
and rinse clean. 

Then apply with a brush, and rub well through the fur down 
to the pelt, half an ounce crystallized nitrate of silver, and one 
pint of soft water, and hang in the sun to dry. 

Again apply with a brush, and rub well through the fur, one 
ounce sulphate of potash, dissolved in one pint soft water, and 
hang in the sun to dry, and, when dry, rinse ofi*, and hang in 
the shade to dry, and work occasionally while drying. 

Method and Machine for Dyeing the Wool on Sheep-Shins. 

Alexander Jack, of Barnet, Yt., in 1875 patented the apparatus 
shown in Fig. 292 for dyeing the wool on sheep-skin, whereby 
the skin is kept perfectly cool during the operation of dyeing, 
thus preventing the skin from being injured, and at the same 
time there is no danger of cooling the dyeing-liquor. The 
invention also consists in a device whereby the apparatus, and 
consequently the skin attached to the same, are kept in the right 
position, so that the wool on the skin can be dyed a number of 
different colors during one operation. 

Fig. 292 is a perspective view of Jack's apparatus with a 
portion of one of the ends removed, and showing the sheep-skin 
in position after dyeing. 

^ is a vat containing the dye -liquor. B B are the guide-rods 
attached to the vat A^ which serve to keep the apparatus, to 
which the skin is attached, in the right position. G is the wool 




TANXIJTG AND COLORIXG WITH THE HAIR ON. 



625 



of the skin after being dyed. D is a strip of cloth hooked on 
points, and to which the skin is sewed. E is a frame which is 
attached to the air-chamber. F is the air-chamber. Q- G are 
the clamps, by means of which the frame containing the skin is 



Fi£. 292. 




attached to the air-chamber. H H are the brackets attached to 
the air-chamber F containing guide-pulleys, which operate in 
connection with the guide-rods B B attached to the vat A. lis 
the space for the escape of the air after being used in cooling 
the skin, t/is a flexible air-tube to convey the air to the air- 
chamber. If is a metal plate to break the force of the wind 
upon the centre of the air-chamber, so that the air in the cham- 
ber will be of uniform density, and be distributed evenly through 
the perforated plate upon the skin. The skin upon which is the 
wool to be dyed is first sewed to the cloth Z>, and then hooked 
to the points. The air is then forced into the air-chamber, the 
wool is lowered and raised a few times in the dye-liquor until 
sufficiently colored, after which it is removed. By means of the 
air admitted to the skin, the latter is always kept cool, and pre- 
vented from being injured on account of coming in contact with 
the hot steam of the dye-liquor, so that it is unnecessary to remove 
40 



626 THE MANUFACTURE OF LEATHER. 

the skin from the vat until the wool is dyed. By the escape 
of the air without coming in contact with the dye-liquor no 
trouble arises in consequence of cooling the liquor. 

By the methods commonly in use but one immersion in the 
dye-liquor is permitted before taking the skin from the vat and 
cooling. It is then returned to the vat and once again immersed 
in the dye-liquor, and again removed from the vat, and this 
operation is continued until the wool on the skin is dyed. This- 
method of dyeing is necessary in the processes commonly 
employed in order to prevent the skin from being injured by 
being too long a time in contact with the heat from the dye- 
liquor. 

By means of the guides B B on the vat, and the pulley- 
brackets U H on the air-chamber, the latter, and consequently 
the skins attached to it, are always kept in uniform position in 
relation to the former, so that, instead of one vat containing 
only one color of dyeing-liquor, several vats containing different 
colors of dyeing-liquors, may be used to receive the air-chamber 
in succession, and the skins thereon be dyed accordingly. 



CHAPTER XLI. 

MINERAL TANNING. 

We understand by this name such methods of tanning as 
those in which mineral substances are employed as tanning 
material instead of vegetable tannin. 

Attemps to substitute mineral substances for vegetable tannin 
were made more than a hundred years ago. 

By consulting the English patent reports it will be seen that 
the use of mineral salts, especially ferraC salts, the tanning pro- 
perties of which were first observed, was already attempted at 
the commencement of the last century. Ashton as early as 1794 
obtained a patent for tanning with ferric salts, which were pre- 



MINERAL TANNIISrG-. 627 

pared bj treating iron rust or iron ores (pyrites) with sulphuric 
acid. Ashton also recommended the heating of other ores, such. 
as copper ores, calamine, etc., with an addition of sulphur, and 
to pulverize and lixiviate the hot mass. Bj heating ores of 
copper, zinc, and iron with, sulphur, sulphur combinations of 
the respective metals are formed which, when in aqueous solu- 
tion, are very likely converted into sulphuric acid combinations, 
in which state they exert a tanning influence upon the skin. 

The specification of the patent, which is very indefinite, 
directs the immersion of the skins in the solution of mineral 
salts prepared as above for five or six days with frequent 
handling. 

Jules Bordier, in 1842, obtained a patent for converting hides 
into leather by means of mineral and earthy substances, recom- 
mending especially ferric sulphate as the most important combi- 
nation. The ferric sulphate was to be prepared by treating 
solution of ferrous sulphate with manganese dioxide or nitric 
acid, with an addition of ferric hydrate. A red salt, not defi- 
nitely described by the inventor, which is separated by boiling 
the mixture, is used for preparing the tanning-liquor. 

Molac and Daniel Triedel, in 1855, obtained a patent, in which 
ferric salts were also described as the tanning material. The 
improvement claimed by them consisted in the neutralization of 
the sulphuric acid, separated in tanning by splitting off from 
the ferric sulphate by means of metallic oxides, such as ferric 
oxides, aluminium oxide, or zinc oxide. 

It is claimed that by this process the skin absorbs more iron 
salts than by using ferric salts alone, and that the injurious effect 
of the free acid is prevented. 

Triedel and Molac prepared their tanning-liquor by treating 
ferrous sulphate with manganese dioxide and sulphuric acid.^ 

To the solution of ferric and manganese salts obtained in this 
manner a varying quantity of ferric acetate was added. 

The depilated and cleansed skins were soaked for 3 or 4 

1 The formula tliey give for this process is according to the old nomenclature : 
4(SOs, FeO) + 2Mn02 4-S03 = 3S03Fe203-f 2(S03MnO)4-Fe203. In this they 
start from the incorrect supposition that the fluid contained free ferric oxide 
and neutral ferric sulphate instead of basic ferric sulphate. 



628 THE MANUFACTURE OF LEATHER. 

weeks iirst in weak solutioDS of the above salts compounded at 
first with some fermented crushed barley, after which the 
strength of the solutions was gradually increased. To neutral- 
ize the free acid, some ferric oxide was from time to time added 
to the solution. By this process it was claimed that the thickest 
hides would in six weeks be converted into leather equal in 
appearance and quality to that tanned in the ordinary manner. 

The next advance in mineral tanning was made by Knapp, 
who, in 1861, obtained a patent in Germany for tanning with 
ferric salts and other metallic oxides. Hides tanned with mine- 
ral substances lost, like those tanned with alum, their tannin by 
immersion in water. Knapp tried to remove this evil by con- 
verting the metallic salts adhering externally to the skin into 
insoluble metallic soaps, by soaking and kneading the skin in a 
soap solution. In order to fix the tanning substance in the skin, 
Knapp recommended, instead of immersing the tanned skins in 
soap solution, the fulling in of insoluble soaps of ferric oxide, 
aluminium oxide, or chromium oxide. The solution of basic 
ferric sulphate Knapp used for tanning was prepared by com- 
pounding the solution with caustic soda until the resulting 
precipitate was again dissolved in the fluid. 

Next to Knapp, Pfanhauser obtained in 1864 a patent for the 
preparation of a basic ferric sulphate and its use for tanning. 
By his process ferric sulphate is heated to a red heat with con- 
stant stirring until the mass is converted into a reddish powder. 
The latter while hot is thrown into water, in which, with con- 
stant stirring, it is almost entirely dissolved. The resulting fluid is 
allowed to clarify by standing, and the clear liquor used for pre- 
paring tanning-fluid of varying strength.. The skins are first 
placed in a dilute solution of 0.5° Beaume, and then succes- 
sively in stronger solution. When thoroughly permeated they 
are washed ofi' and placed in a soap solution. 

The first use of bichromates for tanning was made by Cavalin. 
The skins, according to his method, are placed in a solution of 22 
pounds of potassium bichromate and 44 pounds of alum in 396 
pounds of water, where they remain for four or five days with 
frequent stirring, when they are placed in a solution of 2.2 
pounds of ferrous sulphate in 22 pounds of water. In this they 



MINERAL TANNING. 629 

remain for twelve hours, being in the mean while frequently 
stirred. The potassium bichromate is reduced to chromic oxide 
by the ferrous sulphate, and the ferrous oxide contained in the 
ferrous sulphate oxidized to ferric oxide, both oxides being pre- 
cipitated as such upon the fibre, or the ferric oxide together 
with alumina. The fixing of the chromium combination is 
effected by reducing the soluble chromate to chromic oxide. 
Cavalin's method may be considered as a combination of tan- 
ning with ferric aluminium and chromic oxides. But a practical 
application of the process is not possible, since the leather loses 
its tannin easily when immersed in water, and its grain is 
brittle. 

The use of iron alum and chrome alum was at one time pro- 
posed and actually introduced in practice. But the use of 
these substances was soon abandoned, as the leather prepared 
in this manner had no advantage over that tanned with alum 
and alumina salts. 

All the above-mentioned methods of tanning have been aban- 
doned on account of the defective quality of the product pre- 
pared by them. But this can scarcely be attributed to the 
properties of the tanning material, but rather to the errors 
committed in their preparation. By immersing leather prepared 
with these tanning materials in tan-liquor it was made closely 
to resemble that tanned in the ordinary manner. 

Tanners had almost become accustomed to reject all new pro- 
posals to use mineral instead of vegetable tanning substances, 
justifying their action by referring to former failures, until 
Knapp, in 1877, gave a fresh impetus to the matter by patenting 
in Grermany and other countries a new method of tanning with 
ferric salts. We will first describe Knapp's process as specified 
in the applications for patents. 

Knapp's Process of Tanning with Ferric Salts. 

In the use of the basic sulphate of iron as a tanning material, 
the hides or skins, having the hair and adherent fleshy portions 
removed in the usual manner, are placed in the cold solution of 
the ferric-oxide salt of the proper density, in which they are 
allowed to reniiiin for two, or, at most, four days, during which 



630 THE MANUFACTURE OF LEATHER, 

time it is not necessary to handle the hides in any manner, all 
the laborious operations attending the use of tan-bark liquor, 
while the hides or skins are subjected to the action of such 
liquor, being obviated. At the end of the time named the hides 
or skins are removed from the solution of ferric-oxide salt. 
This salt is prepared as follows : To a boiling solution of sul- 
phate of protoxide of iron (greeu vitriol) is added as much nitric 
acid as will thoroughly oxidize the salt contained in said solu- 
tion. When the effervescence which ensues upon the addition 
of the nitric acid has subsided, the operation is reversed — that 
is, sulphate of protoxide of iron is added to the solution till said 
solution assumes a syrupy consistence — a. distinguishing char- 
acteristic aforementioned — and acquires a yellow- red color, also 
characteristic of solutions of this iron oxysalt, which, when 
slowly evaporated to dryness, has the appearance of an orange- 
red transparent varnish, also highly characteristic. 

In this condition, it is claimed, the ferric sulphate possesses 
qualities differing essentiallj^ from those attributed to it in 
chemical text-books, or found in the commercial article. The 
latter gives no syrupy solution, is of a yellow-brown color, and 
in aqueous solution is decomposed by boiling, while the prep- 
aration produced according to the above method remains un- 
decomposed by boiling even in a solution of 20° to 40° B. It 
is further claimed that the ferric sulphate prepared according 
to Knapp's method is more abundantly absorbed by the skin. 

After tanning, the skins are treated with fat solutions and a 
so-called iron soap. Greasing the skins by hand, hanging them 
up in the drying-room and scraping oft' the excess of fat is done 
away with. Stearine and paraflBne are suitable materials for the 
fat solution. 

The iron soap is separated in an insoluble form by precipi- 
tating soap solution with Knapp's ferric salt. The iron soap pre- 
pared in this manner is mechanically fulled into the skin, a fulling 
drum constructed by Knapp being used for the purpose. This 
machine, shown partly in elevation and partly in section in Fig. 
293, consists of a drum A revolving around the hollow trunnions 
B B\ through which air can be forced into the barrel by means 
of the fan F. 



MIISTERAL TANNING. 



631 



The trunnions are fitted in suitable boxes or bearings G in or 
on a supporting-frame D. 

To one of the hollow trunnions is attached, by a suitable 
joint, a pipe or conductor, E^ which leads from a centrifugal or 
other blower or pump, F. From the inner extremity of the 
trunnion to which the conductor E is attached extend radially 

Fi?. 293, 




outward from the trunnion hollow arms, pipes, or conductors, (r, 
their ends being brought quite near the inner surface of the 
drum J., and their ends near the inner surface being open. 

The joint which connects the pipe or conductor E with the 
trunnion B' is of such a character as to permit the free turn- 
ing of the trunnion on its bearing without turning the con- 
ductor. 

When the apparatus is in operation the leather or tanned 
hides to be greased or treated with soap or other substance are 
placed in the drum A^ which has a suitable opening in its side, 
provided with a cover (not shown) for the reception of the 
hides to be treated, and the proper quantity of the substance to 
be thereto applied is also placed in the drum. The drum is 
then rotated by means of a pulley, gear, or other suitable means. 
At the same time the blower i^ is set in operation, and air is 
driven through the trunnion B' into the drum and discharged 
on the inner surface. The air then passes toward the centre of 
the drum through the interstice.s and pores of the leather in the 



632 THE MANUFACTURE OF LEATHER. 

drum, exerting a rapid drying action on the same, the removal 
of the water in the wet or damp skins being followed by the 
rapid and thorough absorption of the grease or substance it is 
desired to incorporate into the pores of the leather. Finally the 
air issues from the trunnion B. 

A paste of iron soap described above is applied to the skin 
with or without an addition of fatty emulsions, or placed 
together with the skins in the fulling drum and mechanically 
fulled in. The skins are dried at the same time by the current 
of air passing through the fulling drum. The new and peculiar 
features claimed for this process by Knapp are as follows : — 

1.^ The preparation of the ferric salt, especially the treatment 
of the ferrous sulphate oxidized by nitric acid by a 
further addition of the same salt. 

2. The treatment of the skins and hides with solutions of iron 

and fat, 

3. The use of stearin for the above purpose. 

4:} The fulling drum connected with a fan by which a current 

of air is forced into it. 
5. The iron soap and its use. 

The advantages of this method of tanning are, according to 
Knapp — 

1. Greater cheapness (from 5 to 25 per cent.). 

2. Considerable saving of time, the product being of an equal 

quality and durability. 

3. The obtaining of as large a yield as by tanning in the ordi- 

nary manner. 

4. The use of a tanning material of a constant chemical com- 

position by which the obtaining of a uniform product is 
assured. 
The leather prepared by Knapp's process has a brown-yellow 
color closely resembling that of leather tanned in the ordinary 
manner. It is, according to Knapp, not water-proof but capa- 
ble of resisting water, meaning by this that the leather does not 
lose its tannin by frequent contact with water. As far as we 

1 By a decision of the patent office of the German empire, claims one and four 
have been set aside, as not being new. 



MINERAL TANNING. 633 

know, this process lias thus far only been used for the prepara- 
tion of sole and belt leather, and we are unable to say whether 
upper leather has also been lately successfully produced. 

"We will say nothing further pro et contra, in regard to this 
method. 

Knapp has applied for an additional patent for a somewhat 
different method of preparing the ferric salts. Instead of add- 
ing, as formerly described, nitric acid to a boiling solution of 
ferrous sulphate, an equivalent quantity of sulphuric acid and 
sodium nitrate is added to the ferrous sulphate solution. The 
tanning with this is effected in the same manner as previously 
described, but can also be done by the precipitate which albu- 
minous substances, as for instance that of blood, produce with 
the ferric solution. 

Heinzerling' s Method of Tanning with Ghromates^ etc. 

In the years 1880 and 1881, Heinzerling obtained patents in 
the United States, and previously in other countries, for quick 
tanning with chromates with an addition of aluminium salts, 
sodium chloride, etc. 

The process is executed as follows : — 

The skins are cleansed, depilated, and swelled, and placed in 
a one-quarter per cent, solution of chromic acid or in a half per 
cent, solution of potassium bichromate, sodium bichromate, or 
magnesium bichromate or other neutral bichromates, or in a 
half per cent, solution of chromic salts, for instance chromic 
sulphate. It is advantageous to add to the solution one per 
cent, of alum or aluminium sulphate or other aluminium salts, 
and one per cent, of sodium chloride. According to their thick- 
ness the skins remain in the solution a shorter or longer time.^ 
During this time the solution is successively concentrated until 
it contains as much as GJ per cent, of chromates, 12 per cent. 
of alum, and 10 per cent, of common salt. 

The action of tanning-liquors gradually increasing in strength 
can also be effected in a more simple manner by placing the 

' Calf-skins, for instance, four to six days, and lieavy bullock hides up to 
fourteen days. 



63-i THE MANUFACTURE OF LEATHER. 

skins successively in more concentrated solutions and allowing 
them to remain a corresponding time in each of the solutions. 

When fresh skins are placed in the tanning-liquors, the tan- 
ning substance withdrawn by the skins taken out must be 
always supplemented, the quantity required being determined 
by analysis. 

Although experience has shown that the tanning process can 
be executed without the use of aluminium combinations and of 
common salt, it is advantageous to employ thera, since these 
substances possess also tanning properties and accelerate the 
process, and besides being comparatively cheap, reduce the cost 
of the operation. 

If leather is to be produced which is to be blackened after 
tanning, 2 to 3 per cent, of potassium ferric-cyanide or potas- 
sium ferro-cyanide is added to the solution. These substances, 
together with the iron black applied later on, give a deep dark- 
blue color to the leather. 

After tanning in the described solutions, the skins are placed 
in a 4 to 8 per cent, solution of barium chloride, acetate of lead, 
or soap, which effects a partial fixing of the tanning substance 
by the latter forming with the first insoluble salts or soaps. 

To effect a quicker absorption of the barium chloride, ace- 
tate of lead, or soap, the skins, while in the solutions, are vigor ■ 
ouslv moved or kneaded. They are next washed, superficially 
dried and stretched, and, while still feeling somewhat moist, 
placed for 36 hours in a solution of stearine, paraffine, w^ax, rosin, 
colophony, spermaceti, or of other hydrocarbons or fat, in 
benzine or other solvents having a similar effect. 

It is advantageous to heat the solution containing fat, paraf- 
fine, or other hydrocarbons to 96.8° P. in a water-bath. In place 
of stearine or the other substances mentioned, a mass resembling 
caoutchouc can be used, which is obtained by treating oils 
(linseed or rape-seed oil) with 10 to 15 per cent, of chloride of 
sulphur. If chromic acid is used in tanning, the parafi&ne em- 
ployed in the after-treatment is oxidized by the acid, the latter 
being at the same time reduced to chromic oxide. The paraf- 
fine appears to become oxidized to an acid-like combination 
which enters with the chromic oxide, formed into a combination 



MINERAL TANNING-. 635 

insoluble in water which is firmly precipitated upon the fibre. 
When chromates are used, the chromic acid is split off from 
the chromates during the tanning process, either by the skin 
itself or, in case aluminium salts are employed, by the sul- 
phuric acid liberated from them. By the succeeding treatment 
with paraffine, etc., the insoluble combination described above 
is also formed. As a proof of the described action upon the 
paraf&ne taking place, we would mention the fact that the cut 
surface of leather prepared according to the described process 
is at first yellow but becomes gradually lighter, especially when 
exposed to the light, and turns finally to a nearly whitish-green. 
Metallic salts, for instance cupric sulphate and others, can be 
added to the solution of chromates formerly mentioned, partly 
on account of the tanning effect of these salts, and partly in 
order to produce certain shades of color upon the leather. 

The skins can also be placed, either before or after they Lave 
been treated with the described tanning-liquors, in solutions 
containing vegetable tannin. 

After the skins have been removed from the solutions of fat, 
paraffine or rosin, the leather intended for uppers and belts is 
greased in the same manner as leather tanned in the usual 
manner, with a mixture of tallow, train oil, or similar fat mix- 
tures. After greasing, the fat is either fulled in or allowed to 
soalv in by hanging the skins in a moderately heated room. 

The upper leather is, generally speaking, curried in the same 
manner as leather tanned by the ordinary process, a few points 
only requiring special precautions to assure a fine product. 

In preparing black grain leather, it is best to blacken the 
skins before placing them in the fat solutions. For blacking, 
on account of the yellow ground being more difficult to blacken, 
the application must be repeated once or twice oftener than for 
leather tanned in the ordinary manner. 

If the leather is to be blackened after greasing and currying, 
the fat must first of all be thoroughly removed by scouring 
with dilute solution of soda or ammonia, and rubbing with 
pumice stone powder, or wood ashes. The grain side thus 
cleansed is then blackened with logwood extract or iron black. 

Sole leather tanned by the above process, is, after removal 



636 THE MANUFACTURE OF LEATHER. 

from the tanning-liquor, impregnated with solutions of fat, wax, 
or rosin. It is then dried and rolled. 

In working the upper and sole leather into shoes, the follow- 
ing directions should be observed : In order to be able to last 
the upper well, it should be placed in lukewarm soap-liquor 
for 10 to 12 hours and frequently kneaded. Lasting can only 
be accomplished in the ordinary manner after the fluid has 
thoroughly permeated the grain, which is more difficult to effect 
than with leather tanned in the usual manner. Chromium leather 
it is claimed is more water-proof. The property of the leather 
of not stretching after having been worked, deserves special 
attention, since a shoe made a close fit, as is generally the case 
with leather tanned in the usual manner, is apt to be too tight. 

For sole leather to be easily worked it is not sufficient to dip 
it simply in cold water; it should remain for some time in luke- 
warm water. 

As will be seen from a table on p. 88, experiments which 
have been made in regard to the absorption of water by leather 
tanned in the usual manner and that prepared with chromates, 
have shown that the latter absorbs water slower and a smaller 
quantity of it than the former. 

A further advantage of chrome leather is that it possesses the 
property of losing less tannin by repeated treatment with cold 
or warm water than leather tanned in the usual manner. 

We give here comparative experiments as regards the solu- 
bility of the tannin in chrome leather which were made by Dr. 
J. Clark, city analyst of Glasgow. 

In order to establish the total quantity of chromium contained 
in the leather and also the quantity of chromium which was 
under different conditions withdrawn by the action of water, he 
used six samples of chrome leather, namely : Foreign bends ; 
English bends ; heavy sole leather ; strips of sole leather ; bul- 
lock leather, and calf leather. The samples were cut into pieces 
of two inches square, and the resulting percentage of chromium 
calculated as potassium bichromate as follows : — • 

Total percentage of chromium calculated as potassium bichro- 
mate : Foreign bends 3.30 per cent., English bends 3.47 per 
cent., heavy sole leather 3.97 per cent., sole leather strips 4.80 



MINERAL TANNING. 637 

per cent., bullock leather 6.18 per cent., calf leather 3.50 per 
cent. 

The quantity of potassium bichromate withdrawn was as 
follows : — 

a. By boiling with water for half an hour: — 

Foreign bends, 0.005 per cent. ; English bends, 0.048 per 
cent. ; heavy sole leather, 0.006 per cent. ; sole leather 
strips, 0.018 per cent. ; bullock leather, 0.054 per cent. ; 
calf leather, 0.006 percent. 
h. By immersion in cold water for 12 hours : — 

Foreign bends, 0.004 per cent. ; English bends, 0.019 per 
cent. ; heavy sole leather, a trace ; sole leather strips, 
0.006 percent.; bullock leather, 0.022 per cent.; calf 
leather, 0.060 per cent. 

c. By immersion in cold water for 24 hours : — 

Foreign bends, 0.005 per cent. ; English bends, 0.027 per 
cent. ; heavy sole leather, a trace ; sole leather strips, 
0.007 per cent.; bullock leather, 0,043 per cent.; calf 
leather, 0.077 per cent. 

d. By immersion in cold water for six days: — 

Foreign bends, 0.014 per cent.; English bends, 0.091 per 

cent.; heavy sole leather, 0.025 per cent.; sole leather 

strips, 0.017 per cent. ; bullock leather, 0.135 per cent. ; 

calf leather, 0.123 per cent. 

A sample of good leather tanned in the nsual manner and 

obtained from one of the best English tanners on being treated 

in the same way gave the following results : — 

a.^ Withdrawn by boiling in water for half an hour=2.13 
per cent, (containing 0.77 per cent, of tannic acid). 

b. By immersion in cold water for 12 hours=2.99 per cent, 
(containing 1.08 per cent, of tannic acid). 

c. By immersion in cold water for 24 hours=4.45 per cent, 
(containing 3 per cent, of tannic acid). 

d. By immersion in cold water for 6 days= 6.79 per cent, 
(containing 2.55 per cent, of tannic acid). 

' That less extraction occurred by boiling than by immersion in cold water 
for 12 hours is probably explained by the fact that by boiling a part of the skin 
substance is converted into glue, which forms an insoluble precipitate with the 
tannic acid. 



638 THE MANUFACTUEE OF LEATHEK. 

From the above results it will be seen that the quantity ot 
potassium bichromate extracted by immersion of chrome leather, 
even if continued for 6 days, is exceedingly small, and this quan- 
tity, small as it is, is in all probability still further decreased by 
the reducing action of organic substances upon the chromic acid. 

Dr. Clark concludes his report as follows: "I am firmly con- 
vinced that the remainder of the chromic salts cannot be with- 
drawn from the leather by any influence to which it may be 
exposed in use." 

We give in the two following tables the results of two Eng- 
lish experimental stations as to the stretching capacity of chrome 
leather and tan leather. 



MINERAL TANNING. 



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MINERAL TANNING. 641 

The foregoing statement indicates : 1st. that chrome leather 
excels in strength ; 2d, that after reaching the stretching limit 
with a corresponding load, it possesses still a considerable degree 
of elasticity which is of great value as regards the adhesion of 
belts to pulleys. 

Alum inium Ta nning . 

This patented method of tanning originated with Dr. Patz, of 
Passau. The skins are prepared in the usual manner and then 
completely tanned with a solution of aluminium sulphate or 
common salt. After tanning, the tannin, it is claimed, is pre- 
cipitated upon and fixed in the skin by fulling in an insoluble 
precipitate produced by boiling hair, horn, blood, and other 
substances containing albumen, with a solution of potash or 
caustic soda, and precipitating the resulting solution with alumi- 
nium sulphate or other aluminium salts. 

List of all Patents for Employing Mineral Substances for Tawing 
Hides and Skins, issued hy the Government of the United States of 
America, from 1790 to 1883 inclusive. 



No. 


Date. 


Inventor. 


Residence. 


17,955 


Aug. 4, 1857. 


H. Hibbard, 


Henrietta, N. Y. 


21,168 


Aug. 10, 1858. 


T. Klemm, 


Pfullinger, Germany. 


46,443 


Feb. 21, 1865. 


Gr. Bottero, 


Boston, Mass. 


86,506 


Feb. 2, 1869. 


F. Clozel, 


Paris, France. 


159,366 


Feb. 2, 1875. 


W. R. Stace, 


Rocliester, N. Y. 


193,520 
193,521 


July 24, 1877. ) 
July 24, 1877. S 


F. Knapp, 


Brunswick, Germany. 


231,797 
238,389 


Aug. 31, 1880. \ 
Mar. 1, 1881. ) 


C. Heinzerling, 


Biedenkopf, Germany, 


260,322 
260,418 


June 27, 1882. \ 
July 4, 1882. ) 


C. Richter, 


St. Paul, Minn. 


281,411 


July 17, 1883. 


C. P. Smallridge, Sr. 


, Catlettsburg, Ky. 


287,255 


Oct. 23, 1883. 


F. E. Dietsch, 


Woodbury Falls, N. Y 



Note. — For a portion of the matter in this chapter the author desires to 
acknowledge his indebtedness to Heinzerling's Lederbereitung, BoUey's Tech- 
nologie, 35 (Bd. vi. 4). 



41 



642 THE MANUFACTURE OF LEATHER. 



CHAPTER XLII. 

TAWING — FRENCH OR ERLANGER METHOD OF TAWING — DAN- 
ISH GLOVE LEATHER — JENKINS'S METHOD OF TAWING — DE- 
FECTS OF ALUMED VARIETIES OF LEATHER- — MANUFACTURE OF 
OIL OR CHAMOIS LEATHER — PRELLER's METHOD OF TAWING — 
KLEMM's OIL LEATHER. 

French or Erlanger Method of Tawing. 

The manufacture of soft leather for gloves, i. e., the so-called 
French or Erlanger leather, which was originally a French 
industry, has also been lately brought to a high degree of per- 
fection in Germany and Austria, and especially in Prague. As 
these varieties of leather are intended for articles of fashion and 
luxury, they require all the properties of alumed leather in a 
higher degree, according to whether the articles manufactured 
from them are to be a pure uniform white, or a light delicate 
color. These demands can only be fulfilled by using the most 
scrupulous care in preparing the skins, great cleanliness, and 
avoidance of anything which might cause stains, such as the use 
of vessels of oak, water containing iron, etc. It is besides 
necessary that the gloves should possess a more than ordinary 
capacity of stretching, and a high degree of suppleness, while 
they must at the same time be strong and durable, and the grain 
sound and free from all injury. They must further adapt them- 
selves to the hand, and by their capacity for stretching supple- 
ment the natural inaccuracies of the pattern, and, what is the 
most difficult to avoid with such tender skins, not tear in the 
seams or the leather. 

The utmost care in working the raw material alone will 
therefore not suffice, since the quality and availability of the 
leather will largely depend on the quality of the skins. 

Besides conducting the tawing process with care and cleanli- 



TAWING. 643 

ness, a manufacturer who desires to bring into the market au 
article answering all demands, should therefore know how to 
select and buy the skins to be worked. 

We will therefore, before treating of the tawing process 
itself, give a few practical hints as regards the buying and stor- 
ing of skins intended for glove leather. 

Buying and Preserving the Rata Skins. 

The skins most generally used for the manufacture of glove 
leather are those of lambs and kids, together with a few other 
light varieties such as skins of chamois, dogs, etc. The skins 
of unborn, or at least very young lambs, which are brought into 
commerce principally from England and Hamburg, furnish an 
especially fine material for glove leather. 

Generally speaking, kid-skins are preferred to all other varie- 
ties, as they furnish a more tender and a finer variety of leather 
than all others, with the exception of chamois-skins, which are 
also very highly esteemed. Skins of young lambs, especially 
of those not more than one month old, give also a very good 
and flexible leather, though this is not the case with old skins, 
which can therefore be only used for the manufacture of an 
inferior quality. Kid-skins being comparativel}' rare, skins of 
young lambs, the Silesian and Spanish being preferred to the 
Hungarian, Servian, etc., are almost exclusively used for the 
manufacture of glove leather. Large quantities of lamb-skins 
have also been recently imported from South America, especi- 
ally from Buenos Ayres, which, though equal in quality to the 
Hungarian skins, are inferior to the Silesian and Spanish articles. 
As regards dog-skins and cat-skins, which are less frequently used, 
much depends on the age of the animal, and the breed. 

A kid-skin should, in order to be classed as a commercial 
article, measure at least 10 to 10| inches square ; of the smaller 
skins three are generally counted for two, or even two for one. 

As regards lamb-skins, those from long-wooled species are 
the l?est. The skins of half- blooded breeds have but little 
value for the manufacture of glove leather, and those of full- 
blooded stock none whatever, as they are usually very thin and 
porus, and have but little strength, on account of the epidermis 



644 THE MANUFACTURE OF LEATHER. 

being generally imperfectly connected with the true skin. The 
great difference in the quality of these skins is partly due to the 
sheep themselves, and partly to the food. It may, however, be 
laid down as a general rule, that the coarser the wool the better 
the skin for the manufacture of glove leather. 

By crossing he-goats and ewes a bastard breed is obtained, 
the skin of which, though bearing wool, approaches that of kid, 
and furnishes good material for glove leather. 

The price of lamb-skins, which varies very much, depends 
largely on the quantity and fineness of the wool, and the size 
and quality of the skin itself. 

After the lambs or kids are weaned, and commence to eat 
other food, the skin gradually loses more and more of its beauty 
and suppleness, and consequently its value for glove leather. 
The skin of a lamb fed partly on the milk of the mother and 
partly on other food, loses comparatively little in quality. A 
good skin should be smooth and lustrous, and slightly trans- 
parent without being too fat. 

After procuring the required stock of skins, the tanner pro- 
ceeds to sort them according to derivation, size, and age. A 
large stock of skins should never be stored away without 
previous sorting, since, after a lapse of time, it will not be 
possible to tell accurately the age of a skin nor its derivation, 
while it is of the utmost importance for the production of good 
leather to use for any tawing process only skins as uniform 
as possible. 

The skins, after sorting, are stored in a dry and airy loft or 
shed. While stored they are exposed to many dangers, espe- 
cially during the hot season of the year. Among the principal 
injuries to which skins are subjected while stored, we may 
mention such as arise from heating and the attacks of moths. 

Heating, to which kid skins are especially exposed, is actually 
nothing but the appearance of a superficial putrefaction 
attended, in consequence of the skins being closely piled, by a 
more or less strong heating which materially promotes the de- 
composition already commenced. As skins not entirely dry 
before storing are principally affected by this evil, special atten- 
tion must be paid to the thorough drying before piling upon 



TAWING. 645 

eacli other. But even witli entirely dry skins, the tanner should 
assure himself from time to time, by an examination of the sep- 
arate ones, that heating has not made its appearance, and to stop 
the evil immediately, in case he finds the slightest indication of 
it, hy spreading the respective skins in the sun or in a dry and 
airy place. Although a slight heating of the skins, such as is 
frequently observed during damp weather, effects no material 
injury, too much of it will certainly cause considerable damage. 
Heating renders them soft, spoils the grain, and causes the wool 
to fall out. Although these injuries may frequently not be ob- 
served at once, they will be only too plainly perceived in the 
after-treatment of the skins. 

The damage by moths is caused by the deposits of larvae of 
certain moths in the wool of the skin. 

From the middle of spring to the end of summer small, silver 
gray butterflies are observed, especially in the evening, flying 
around in the houses. These are the genuine moths appearing 
most frequently in July and August. These nocticidse take no 
nourishment and possess no weapon with which they could 
cause damage. Their only object is to form a sexual union, and 
this being accomplished the female lays its eggs upon clothing, 
furniture, etc., but preferably upon wool or fur. The eggs are 
so small as to be scarcely perceptible with the naked eye. The 
larvae make their appearance in a few weeks, sooner in warm 
weather than in cold. Only the eggs and larvse can stand the 
cold of winter. 

Although the moths themselves are generally known, this is 
not the case with the larvae, as they live in hidden places and 
are so small and insignificant as to escape observation. It may, 
therefore, not be inappropriate to give here a short description 
of these enemies of wool. The extremely small grub of the 
moth, which externally does not differ materially from other 
larvae, is provided on the forepart of the body with three pairs 
of horny feet, which together with the mandibles and a part of 
the scutellum, form the only horny part of the body. The first 
business of the grubs after emerging from the eggs is the con- 
struction of a cocoon. For this purpose they weave first a thick, 
spindle-shaped tube around their centre, and enlarge this tissue, 



6^Q THE MANUFACTURE OF LEATHER. 

consistiDg of delicate silk-like threads, by biting off with their 
mandibles the hair of the wool or fur surrounding them, and 
attaching them with a sticky substance secreted by them. 
This cocoon, which is open on both ends, has the same color as 
the wool or the hair of the skin, or the tissue in which the grub 
lives. In the same degree as the grub grows, the cocoon be- 
comes too short and narrow. When this is the case the grub 
projects the fore-part of its body from the cocoon and, after bit- 
ing off with its mandibles the wool or hair within reach, and 
enlarging the cocoon on that end by gluing the wool to it, 
turns around and performs the same operation on the other end. 
To widen the cocoon the grub gnaws through the entire length 
and inserts a new piece by gluing in wool or hair. When the 
grub has nearly attained its full growth, and the time of meta- 
morphosis approaches, it leaves its place of concealment and 
moves into the open air where, after attaching one end of the 
cocoon to a wall, woodwork, etc., it changes to a chrysalis. The 
perfect moth emerges after three weeks, during which time the 
chrysalis does not leave its place of abode. While the grubs of 
the genuine moth carry their cocoon with them, there are 
others, for instance, the ascarides, which build permanent cocoons 
in the form of passages of greater or less length on the base of 
the fur in which they live. The damage done to the skins by 
these insects not only consists in the destruction of the wool, 
which would be of little consequence, but in injury to the skin 
itself by the perceptible traces they leave upon it which damage 
the grain and quality of the leather. 

The best means of getting rid of these insect pests is to air 
the skins every eight or ten days during the hot summer 
months, and, if possible, beating them thoroughly in order to re- 
move any larvae alread};- in the wool. In cold weather beating 
every three or four weeks suffices. To be successful it is not 
sufficient to beat the bales, but each skin must be handled sep- 
arately. To avoid this work which, though sure, is very tedi- 
ous, many preservatives have been recommended, for instance, 
placing powdered pepper, the blossoms of Eoman camomile, 
leaves of patchouli, etc., between the skins, or sprinkling them 
with carbolic acid, spirits of camphor, etc., or scattering insect 



TAWING. 647 

powder or sumach upon them. The best of these means, none 
of which is entirely effective, is perhaps carbolic acid or a mix- 
ture of birch oil and camphor, but they impart to the skins a 
penetrating odor which is not lost even by the succeeding treat- 
ment, and can only be got entirely rid of by long continued 
airing. 

Manner of Working the Shiyis. 

The principal difference between the ordinary and French 
method is in the actual tawing process and the means used to 
accomplish it, the preparatory labors being in the main the 
same. 

The work of tawing leather according to the French or Er- 
langer method is divided as follows: — 

1. Soaking and Ritising. 2. Liming and Depilating. 3. 
Treating with hate. 4. Handling in the bran vat. 5. Tawing in 
the tawing comjoound. 6. Finishing . 

1. Soaking and Rinsing. 

As previously mentioned, it is of great advantage for the 
manufacture of good glove leather to work skins in as nearly the 
same manner as possible, in order to obtain a nearly uniform pro- 
duct. This should be taken into consideration at the commence- 
ment of the work by soaking skins as nearly alike as possible and 
their differing not too much as regards age. Soaking and rinsing 
are effected either in running water, or if possible in the "soaks." 
The soaking is continued until all the skins are uniformly soft 
and freed from adhering dirt and blood, and thoroughly cleansed 
on the flesh side as well as on the wool side. In order to obtain 
clean wool, which is more salable, the wool side is frequently 
scrubbed with soap, though this labor is of course omitted in 
handling very young lamb-skins, the wool of which has no 
commercial value. 

In soaking and rinsing, special care must be had to have the 
water free from impurities, especially mud and iron, and not to 
use vats of oak, but of soft wood. In regard to the duration of 
soaking we will state that, as the skins of young animals, such 
as kids and lambs, have to be chiefly taken into consideration, 



6i8 THE MANUFACTURE OF LEATHER. 

three days in winter, and at the utmost two days in summer 
should suffice for the process. 

After soaking and rinsing the skins are subjected to the 
breaking process, which is effected in the same manner and with 
the same tools as in ordinary tawing. A clean beam and a 
fleshing knife free from rust, and not too sharp in order to 
avoid injury, are required. In breaking the skins their great 
tenderness and susceptibility to injury must be taken into due 
consideration. 

After breaking and another rinsing, the skins are ready for 
depilation. In most places this is proceeded with at once, while 
in some taweries the skins are placed in bate for two to twenty- 
four hours to make them more susceptible to the action of the 
lime and accelerate the loosening of the hair. 

2. Liming and Depilating. 

It is usual to consider 13 to 15 pounds of thoroughly burned 
limed, slacked to milk of lime, as being required for 100 goat- 
skins, or equally large lamb-skins. The process of liming is 
conducted either by using several lime-vats with lime water of 
different strengths, and putting the skins successively from the 
weakest lime-vat into the strongest, or what is more generally 
the case, by employing but one lime-vat and increasing gradu- 
ally the concentration of the lime water. For the latter purpose 
the entire quantity of lime to be used is generally divided into 
four equal portions, and the lime-vat, which is generally filled 
with lime water previously used, is charged for the first liming 
with one quarter of the entire quantity of lime. 

After thorough stirring throw each skin separately into the 
vat so that it falls with the wool side down upon the surface of 
the milk of lime, and push down with a pole. 

In this vat the skins remain, according to size and age, for 
one to three days, though in winter they are generally allowed 
to remain somewhat longer. The skins are then lifted out with 
wooden tongs — iron tongs must be absolutely forbidden — and 
hung upon the edge of the vat to drain off. 

After preparing milk of lime from a second quarter of the 
lime, with the avoidance of too great an excess of water, and 



TAWING. 649 

adding tliis to the lime-vat, the skins are replaced in such a 
manner that those previously on the top come now on to the 
bottom. The skins after remaining in this vat for two to four 
days according to the season, are taken out and allowed to drain 
off. After converting the third portion of the lime into milk of 
lime and adding this to the vat, the skins are replaced. After 
4 days they are again taken out, allowed to drain off, and 
replaced after adding the milk of lime prepared from the last 
portion of the lime. In this vat the skins may remain 6 to 
8 days, but must be handled every 24 hours and replaced in 
reverse order. During this time the skins should be frequently 
examined, and those, where the hair or wool is found to yield, 
removed. 

After removal from the lime-vat and rinsing in clean water, 
the skins are placed in clean water and depilated successively, 
and after depilation thrown into a vat filled half full of water. 

In depilating the greatest care must be observed to avoid 
injuring the grain by too strong pressing, and to be able to do 
this, the skins should not be taken from the lime- vat until the 
hair or wool is thoroughly loosened. 

The method above described is principally employed for kid- 
or young lamb-skins. Frequently a mixture of orpiment and 
lime, or of gas-lime and lime, is used for loosening the hair. 

For depilating the skins of older animals, especially those 
over a year old, the sweating process previously described is 
generally employed. But in order to yield supple leather such 
skins must, after depilation, be placed in the lime-vat for 3 to 4 
days. The skins are then topped or docked, and, after break- 
ing them upon the beam and cleansing, are thrown into a vat 
filled with water. To prevent the skins from becoming spotted, 
they must at no time be allowed to remain long oat of water. 

3. Treatment in Bate of Dog Excrements. 

This work is frequently connected with the so-called fulling, 
and sometimes entirely replaced by the latter. As regards the 
preparation and use of the bate we refer to what has been said 
about it under tanning, only calling attention to the fact that 



650 THE MANUFACTUEE OF LEATHER. 

the action of the bate must be shortened in accordance with the 
weaker texture of the skins.^ 

After removal from the bate, the skins are either at once 
broken and rinsed or first fulled. For the latter purpose 300 
to 500 rinsed skins are placed in the fulling trough and pounded 
thoroughly with a rounded-off" wooden mallet. After a quarter 
of an hour a bucketful of clean water is poured into the trough 
and the fulling continued for twenty minutes longer, when an- 
other bucketful of water is poured in and the fulling again con- 
tinued for twenty minutes. The skins are then placed in a vat 
full of clean water for one to three days according to the season 
of the year. 

The fulling can also be effected with a washing wheel such as 
is frequently used by manufacturers of Morocco leather. 

A washing wheel much used in Germany and France is ar- 
ranged in the following manner: A wooden drum, with a 
diameter of ten feet and a width of rim of three feet four inches, 
lies with its horizontal axis in brass boxes, and motion is im- 
parted by means of a crank or driving gear. The drum is 
shown in Figs. 294 and 295, and the interior is divided by parti- 
tions into three or four compartments in such a manner that 
each compartment is accessible from the exterior through a 
large aperture, d, in the rim of the drum, which serves for the 
introduction of the skins and can be closed with the slide i. 
Short cross ribs projecting towards the centre are arranged on 
the arch of the compartments, i. e., on the inside of the rim, 
which is perforated with fine holes. The outside of the rim is 
provided with small laths nailed on zig-zag. The object of 
these, and of the laths on the edges of the rim, is to prevent as 

1 In most taweries the bate is generally prepared by soaking dog excre- 
ments in water and stirring them to a uniform paste, of which 2^ to S^- gallons 
mixed with a sufficient quantity of water of 95° F. are used for 1000 young 
lamb-skins. The depilated skins remain in the bate for about 3 hours, or at 
the utmost until the remnants of flesh can be readily detached. The skins 
sufl'er injury by remaining too long in the bate. 

We would here call attention to the fact that dog excrements are frequently 
adulterated with human excrements. Tlie tanner should be very careful in 
regard to this, since the abundance of bilious coloring matter in human excre- 
ments is apt to cause the finished leather to be spotted. 



TAWING. 



651 



mucli as possible a waste of water falling from the rose A, which 
is placed above the drum. 



Fig. 294. 




Fi^. 295. 



The manner of using the drum for fulling is as follows : The 
drunx, after placing the skins in the different compartments and 
closing the slide, is set in motion and 
water allowed to fall continually 
through the rose upon the rim of the 
drum. The manner in which the 
machine works is self evident. The 
skins in the compartment occupying 
the lowest position during the revolu- 
tion of the drum lie upon the arch, i. e., 
the inside of the rim provided with 
projecting ribs. They remain here 
until by the upward movement of 
that part, they fall, by gravitation, 
towards the interior upon one of the 
partitions, and by the downward 
movement back upon the arch. By 




652 THE MANUFACTURE OF LEATHER. 

this continual falling backward and forward, the skins are sub- 
jected to an action having the same effect as a gentle beating. 
During the upward movement they are at the same time con- 
stantly washed by fresh water falling into the drum from the 
rose, while the dirty water runs off on the compartment attain- 
ing its lowest position. These operations effect mechanically a 
complete removal of the lime soaps and other lime combinations 
from the skins and wash them thoroughly, and assist materially 
the action of the bate, the object of which is to produce the 
same results chemically.^ 

After removal from the bate or fulling drum, the skins are 
scraped upon the grain side with a dull scraping knife, and then 
rinsed in clean water, the latter operation being more effectively 
accomplished by another treatment in the fulling drum. The 
next operation is to break them upon the beam by working 
upon the flesh side with a sharp fleshing knife in order to re- 
move the last adhering remnants of flesh and fat tissue. They 
are then rinsed and finally scraped again upon the grain side, 
this being, if necessary, repeated after rinsing. Generally only 
heavy skins, especially goat skins, require this repeated scrap- 
ing and fulling. Light skins, such as kid, and young lamb- 
skins, cannot stand, nor do they require, scraping twice, allow- 
ing them to remain only for a short time in the bate and fulling 
drum being generally sufficient. A thoroughly worked skin 
shovild, on being taken from the water, fold together like soft 
cloth, be elastic and at the same time tough and have a uni- 
formly white or greenish-white appearance without spots. The 
next operation is — 

4. Branning . 

The bran menstruum by means of which the skins are raised 
and the last traces of lime removed from the skin tissue, in con- 
sequence of the free acids formed by fermentation, is prepared 
and used in a similar manner as in ordinary tawing. Due con- 

1 Manj' tawers add some soda to the water used for fulliBg the skins, or draw 
the skins, after removal from the bate of dog excrements, through a weak 
solution of soda. 



TAWING. 653 

sideration should be given to the great tenderness of the skins 
and great care exercised to prevent too much raising and possi- 
bly total destruction. 

The bran used in preparing the menstruum should be as fresh 
and pure as possible, and especially free from sand and dust. 
For 100 medium sized skins, soak 2| pounds of bran in cold 
water, and let it stand 3 or 4 hours with frequent stirring. The 
water with a large part of the impurities floating upon the sur- 
face, or held in suspension, is then poured off. On to the 
washed bran pour as much water as will cover the skins to be 
treated, and, after thorough stirring, add 9 ounces of pure com- 
mon salt.^ In this steep the skins remain for 10 minutes when 
they are turned, and allowed to rest after securing their entire 
immersion by weights or cross-pieces of wood. The temperature 
of the menstruum should never sink below 50° F., nor rise much 
above 68° F. In the first case the temperature is raised by an 
addition of warm water, and lowered in the latter case by add- 
ing cold water. 

Great care should be observed in not carrying on the fermen- 
tation too vigorously, and in preventing the appearance of a 
putrid odor, as otherwise the raised skins would easily suffer 
destruction. When sufficiently raised, the skins are taken from 
the liquor and washed in fresh water, or placed upon the beam 
and scraped upon the flesh side, the latter being especially pre- 
ferable to mere washing in case the skins should be raised too 
much, it being possible to reduce this evil somewhat by scrap- 
ing.^ The next operation is — 

5. Tawing. 

The object of this operation is not only to taw the skins but 
to treat them at the same time with the oil required to make 
them supple, and subject them to the action of flour, which im- 
parts to good glove leather its characteristic fulness and soft- 
ness. The tawing paste generally used consists of a mixture of 

1 In many taweries this is omitted. 

2 We would here remark that many tawers, in case they have treated the 
skins with a bate of dog excrements, do not use this bran steep. 



654 THE MANUFACTURE OF LEATHER. 

solution of alum and common salt with yelk of egg and fine 
wheat flour. The following recipe for its preparation may be 
especially recommended : — 

For 100 medium sized skins dissolve IJ pounds of common 
salt, and 5J pounds of alum entirely free from iron, in 9 pounds 
of boiling water. Then make a paste by stirring gradually into 
14J pounds of the best wheat flour, and a little cold water, the 
yelks of fifty fresh eggs. Knead the paste in small portions 
with a gradual addition of water, until it has become thinly 
liquid; the formation of lumps need not be feared when 
brought in contact with more water. Then add 9 pounds more 
water to the paste, stirring constantly and vigorously, and 
finally mix it with the hand-warm solution of alum, and com- 
mon salt. The skins are then placed in a vat, and after pouring 
the lukewarm paste over them, worked thoroughly with the 
hands to moisten them uniformly. When this is done a thor- 
ough penetration of the paste into the skin tissue is effected by 
a workman with bare feet stepping into the vat and treading 
the skins slowly but vigorously by alternate raising of the feet. 
This treading, for which no suitable mechanical appliances have 
thus far been invented as a substitute, is continued until the skins 
have absorbed most of the paste, which for thin skins will require 
1 to 1^ hours and for thicker ones about 2 hours. The vat is 
then covered with a clean cloth, and, after allowing the skins 
to rest for 12 to 14 hours, the treading is repeated in order to 
make them thoroughly smooth and supple. To promote uni- 
form treatment it is recommended to turn the skins occasionally 
during the treading, and, to secure uniformity of the product, it 
is not advisable to subject more than 500 skins to the process 
at one time. 

After the second treading, during which it is customary in 
some places to pour off the remainder of the tawing liquor and 
replace it by lukewarm water, the skins are allowed to rest for a 
few hours, and are then stretched before drying. The object of 
stretching is to effect a uniform extension of the skins, which by 
the treatment in the tawing paste have become somewhat 
wrinkled. Two workmen, standing opposite to each other, take 
hold of each end of the skin and, after folding it grain side in. 



TAWING. 655 

Stretch it as mucli as possible lengthwise. For drying, the 
stretched skins are suspended on poles, or fastened to strings by 
means of pins in such a manner that they hang free for almost 
their entire length. The latter method is preferable, as in the 
first the portion of the skin lying upon the pole will almost 
always turn out somewhat thicker, and besides become easily 
spotted in dyeing in consequence of the tawing paste piled up 
in these places. The principal point in drying is to effect it as 
quickly as possible, and for this reason the skins should be 
hung up in airy lofts which can be heated in damp weather. 
Skins drying slowly spot easily, or acquire a reddish shade 
difficult to remove. 

Instead of the yelk of egg many tawers use olive oil as an 
addition to the tawing paste. This gives also a very supple and 
soft leather, provided the workman understands how to divide 
the oil very finely and to mix it intimately with the tawing 
paste. This is done by rubbing together in a mortar, such as 
druggists use, 2^ pounds of the best wheat flour with sufficient 
water, or still better, thin gum mucilage, to form a stiff paste. 
Add to this drop by drop and very gradually, and stirring con- 
stantly with the pestle, 10 ounces of the best olive oil, and rub 
the mass until a sample mixed with a little water separates no 
globules of fat after continued standing. The mass, the prepa- 
ration of which is rather tedious, prepared in the above propor- 
tions contains an equivalent of about 100 yelks of eggs, and is 
mixed with the tawing paste in the same manner. A still more 
perfect emulsion is prepared by stirring gum arable finely pul- 
verized, instead of wheat flour, into a thick paste with water, 
and adding to this the oil with constant stirring and rubbing. 

About IJ pounds of gum arable will suffice for 9 ounces of 
oil. The use of this substitute for yelk of egg, though quite 
profitable, can only be recommended for inferior qualities of 
leather, and can only be rendered harmless by treading the skins 
a second time in clean water in order to remove the adhering 
gum substance, which otherwise would injure the softness of the 
leather in drying. 

Another mixture suitable for a substitute for yelk of egg, 
which is sometimes difficult to procure, can be prepared by 



656 THE MANUFACTUEE OF LEATHEE. 

mixing intimately 8 J ounces of fresli almond oil, 8 J ounces of 
fresh casei'ne (such as is brought into the market under the 
name of curds), 12| ounces of dextrine, 1 ounce of borax. The 
mixture is effected by putting the caseine in a stone-ware mor- 
tar and pouring over it the borax dissolved in as little boiling 
water as possible. After placing the mortar in a warm place, 
the hot mass is rubbed together until the caseine is almost dis- 
solved and a tenacious liquid drawing threads is formed. To 
the borax and caseine then is next added, with constant rubbing, 
the pulverized dextrine, and after forming a uniform paste, the 
almond oil is added, drop by drop, and the rubbing continued 
until after about three-quarters of an hour the oil has been 
thoroughly mixed. The paste thus obtained can be diluted by 
slowly adding water, and the previously prepared wheat flour 
kneaded with it. A mixture of the above proportions answers as 
a substitute for 100 yelks of eggs, and can, as has been proved 
by many experiments, be used for the finest qualities of leather.^ 

Besides the above, many other substitutes for yelk of egg are 
used, and have been recommended. 

In Parisian taweries calves' brains, intimately mixed with 
wheat flour, are used as a substitute for yelk of egg, ^ oz. of 
brains being generally allowed for 1 yelk of egg. The brains 
of sheep and even of cattle are also used for this purpose, they 
being the more available the younger the animals from which 
they have been derived. In using such brain substance, it is 
recommended, in order to remove the bloodvessels, to rub it 
through a wire sieve with fine meshes, or to press it through 
large cloths. 

According to Knapp, paraffin also furnishes an available substi- 
tute. He uses crude paraffin oil intermixed with crystals of 
j^araffin. This, after heating until the crystals dissolve, is rubbed 
to an emulsion with starch-gum, and the resulting mixture 
compounded with salt, alum, and flour. This tawing paste 
imparts, it is claimed, a beautiful grain to the leather and suffi- 
cient stretching capacity. 

• In using tliis mixture it is recommended to substitute for the alum in the 
tawing -paste a corresponding quantity of aluminium sulphate. 



TAWING. 657 

In many tavveries it is customary to substitute oil for a part 
of the yelk of egg by using about 2 tablespoonfuls of olive oil 
for each 20 yelks of eggs. In this case an intimate mixture of 
the yelk of egg with the oil, which can be easily effected by 
adding some flour, is absolutely necessary, as otherwise the 
spotting of the leather can scarcely be avoided. 
. In regard to the object of using a tawing paste such as plays 
a prominent part in the manufacture of French glove leather, 
the two never wanting constituents, alum and common salt, 
fuliill the same functions as in ordinary tawing, i. e, the alum is 
the actual tawing substance, while the effect of the salt is to 
promote the endosmose. But what eft'ect do the yelk of egg 
and the flour produce ? 

Every practical tawer knows that the object of the yelk of 
egg is to impart suppleness to the leather, and there can be no 
doubt that it fulfills the purposes. Researches have shown that 
100 parts of yelk of egg contain — 

Water .... 48.4 parts by weight 
Albumen .... 20.6 " " 



Yellow oil of egg . . 31.0 



a 



100.0 " " 

As neither water nor albumen possesses the power of impart- 
ing suppleness to leather we must assume that the fat contained 
in the yelk, i. e, the oil of egg, is the effective agent. From the 
fact that yelk of egg has been shown to be decidedly the best 
means of obtaining supple leather, we might naturally come to 
the conclusion that the oil of egg is, on account of its constitu- 
tion, especially adapted for this purpose, or possesses properties 
not belonging to other oils. But this is by no means the case, 
and from the possibility of substituting other suitable mixtures 
for yelk of egg, it is clear that other fats properly prepared and 
used produce the same effect. The valuable qualities of yelk of 
egg are not found in a special constitution of the oil of egg, but 
are based upon other causes. We have already laid stress upon 
the fact that in preparing Erlanger or French leather it is abso- 
lutely necessary to have the fat finely divided before bringing 
42 



658 THE MANUFACTURE OF LEATHEE. 

it in contact with the leather. Fats mix with aqueous fluids 
with difficulty or not at all, and after an artificial mixing has 
been effected, a separation of the fat from the aqueous fluid will 
sooner or later take place. For producing a permanent mixture 
of fat with an aqueous solution, the latter must possess the 
property of preventing the union of the small globules of fat 
suspended in it without changing the constitution of the fat 
itself. 

This property is especially possessed by ropy and thickly 
fluid liquids, and for this reason it is possible to give water to a 
certain degree the power of mixing intimately and permanently 
with fat by adding gum and similar bodies, and also albumen, 
etc. But such artificial emulsions are not entirely permanent. 

Though gum mucilage, albuminous fluids, etc. render the 
running together of the globules of fat more or less difficult, 
they do not prevent it entirely, since the fat divided in such 
artificial emulsions separates from it after long standing. But 
this is not the case with yelk of egg which contains the fat in 
microscopically small globules enveloped in a film of albumen. 
As long as the envelopes are not removed or broken by artificial 
means, a union of the globules of fat is not possible, yelk of egg 
being therefore a natural and very complete emulsion of the oil 
of egg in an albuminous mass, which can be diluted with water 
without destroying the films enveloping the separate globules 
of fat. 

Independent of any other advantage the yelk of egg possesses 
that of being very convenient, since every other fat to be used 
for the same purpose requires tedious and time-consuming work 
for its fine division, while the former offers an emulsion ready 
made by nature. Having shown the advantages of the use of 
yelk of egg, it still remains for us to answer the question: 
What is the object of introducing fat into the skin tissue, and 
what effect does its presence produce upon the tissue of the 
leather? 

By assuming leather to be a skin tissue the fibres of which have 
lost all power of adhesion, and designating such leather as supple 
in which an easy shifting and moving of the tissue fibres, which 
are liable to friction on many points, are accomplished, the signifi- 



TAWING. 659 

cation of fat in the tissue will be clear. The fibres, on the one 
hand, are rendered supple by the fat enveloping them, and, on 
the other hand, the friction produced by the moving and shifting 
of the fibres is reduced to a minimum by the intermediate layers 
of fat. By the word "/««;" we should of course not understand 
an unaltered substance, but rather the products of decomposi- 
tion gradually formed by the action of atmospheric oxygen. 

Independent of the specific action of the fat oil contained in 
yelk of egg, it would seem that the albumen of the latter, besides 
serving as a means of division and a carrier of the emulsion, ful- 
fills another function. This much seems to be proved by experi- 
ments of Knapp, who has shown that the precipitate produced 
by alum from solutions of albumen is easily and completely 
absorbed by the skin when kneaded with it, imparting to it a 
certain degree of tawing. According to this, the albumen con- 
tained in the yelk of egg would, on forming a combination with 
the alum or the alumina contained in it, pass into the skin 
tissue, and by depositing itself upon the separate fibres, assist 
not only in effecting a complete tawing, but increase at the 
same time the fullness and consequently the strength of the 
leather. 

The attainment of a certain fullness seems, however, to be 
essentially the task of the third constituent of the tawing paste, 
viz., the flour. The opinion was formerly entertained, that the 
object of adding flour to the tawing paste was to obtain as white 
a leather as possible. But this is only true in an indirect sense, 
since the actual part the flour takes in the tawing process is an 
entirely different one. Independent of some constituents, which 
are of minor interest to us, we have only to consider the more 
prominent constituents of flour, i. e,, the starch and so-called 
gluten. Of these, starch, a hydrocarbon found in small white 
granules in the cells of plants, is well known. 

Gluten being less known, we will mention here, that by this 
name is designated a constituent of the seeds of almost all varie- 
ties of grain, and it is a mixture of two albuminous bodies known 
as vegetable fibrine and vegetable glue. As, according to this, 
flour is a mixture of several bodies, the question we must pro- 
pose is, whether all the constituents of the mixture take part in 



660 THE MANUFACTURE OF LEATHER. 

the tawing process, or, if this is not the case, which are of the 
most importance. 

The opinion was formerly generally entertained, that the 
availability of the flour depended on the starch, but at present 
there can be no doubt that the eftect of the flour is due to the 
gluten. Knapp has shown by suitable experiments that leather 
tawed in a paste containing flour contains no starch whatever, 
but that the combination of the gluten, or, as previously men- 
tioned, of albuminous substances in general, with the alumina 
of the alum, is absorbed by the skin and may even completely 
taw it. The action of the flour in the tawing paste is therefore 
easily understood. 

The albuminous bodies in the flour combine with the alumina 
in the alum added to the tawing paste, and the combination thus 
formed is deposited, after passing into the skin, around the 
fibres of the tissue in the form of a loose voluminous precipitate, 
which, by augmenting the body of the separate fibres, imparts 
to the entire tissue a certain degree of fullness. Although the 
principal effect of the flour must, according to- this, be attributed 
to the gluten, the starch is by no means an unimportant con- 
stituent. 

Knapp, in his manj^ experiments in regard to tanning and 
tawing, observed that certain combinations of alumina obtained 
as delicate voluminous precipitates by precipitating proteids 
with alum, form lumps when an attempt is made to knead them 
into the prepared skin and lose their capacity of penetrating 
into the skin tissue. To overcome this evil, the presence of 
another indifferent body is required which, by depositing its fine 
particles between the interspaces, prevents the particles of the 
combination from approaching each other and forming lumps. 
This is the part the starch has to perform, which, though it is 
not absorbed by the skin tissue, is capable of keeping the parti- 
cles of the combination of alumina with gluten apart until they 
have penetrated the skin tissue and taken their proper position. 
This explains why flour cannot well be replaced by other 
means. 

To recapitulate briefly what has above been said the object 
of the mixture of alum, common salt, flour, and yelk of egg or 



TAWING. 661 

its substitutes is, besides tawing, which is due to tlie alum and 
the conaraon salt, to impart softness and suppleness to the leather 
and finally fullness, the yelk of egg serving specially the pur- 
pose of obtaining suppleness and the flour fullness. 

After treating with the tawing paste and drying thoroughly, 
the leathers can be stored without danger in a dry place. They 
require only 

6. Finishing, 

the object of which is, on the one hand, to remove the last rem- 
nants of adhering tissue fibres, and, on the other, to impart as 
high a polish as possible and a delicate smoothness to the leather. 
The first operation is stretching the moistened leather. For 
this purpose the skins are sprinkled separately with water, and 
after stretching evenly upon a level table, they are piled upon 
each other and allowed to lay for some time until they are uni- 
formly moist. About 12 to 15 of these moist skins are then 
piled upon a linen cloth upon a straw mat, and after being cov- 
ered with a clean cloth or a large skin especially kept for the 
purpose, softened by a workman treading them. Each skin is 
then subjected to stretching by a workman holding it distended 
by both ends and drawing the flesh side in every direction over 
the stretching iron in order to remove as much as possible all 
remnants of adhering tawing paste. The skins are then 
stretched on poles, dried, and, after repeating the treading and 
drawing over the stretching iron, rubbed upon the grain side 
with a soft woollen rag to remove any adhering flour. Skins 
which are to remain white, or to be dyed a light color, are fre- 
quently bleached by exposing them to the sun for several 
hours. This is not required for skins to be dyed dark. 
Although leather finished in this manner is ready for the 
market, it is frequently subjected to glazing. The object of 
this operation is to make the grain side as smooth as possible, it 
being sufficient for sound and thoroughly tawed skins to pass 
them through the smoothing roller, although in large factories 
special smoothing machines are used. 

The polishing is generally accomplished with a polished steel 
or agate roller set in a crutch handle and revolvino; around its 



662 THE MANUFACTURE OF LEATHER. 

axis, as shown in Fig. 296. After spreading the skin, flesh side 
down, upon a table with a smooth wooden or stone plate, the 
workman passes the roller repeatedly and forcibly over the 
grain side of the leather. By this operation any little irregular- 
Fig. 296. 




ities injurious to the appearance of the leather and making it 
feel rough to the touch, are removed from the grain side, and 
the leather rendered smooth and to a certain degree lustrous. 

The same effect is produced by the use of a large polished 
glass or stone ball, although, as the workman has to guide the 
ball with the hand, and cannot exert as strong a pressure as with 
the smoothing roller, the process is tedious, and consequently 
less suitable. The use of heated rollers is very advantageous. 
For this purpose the steel rollers are heated either by placing 
them in boiling water or by means of a spirit flame, care being 
had not to heat them too much, as otherwise the leather might 
be burned or become wrinkled. 

We had occasion to become acquainted with a polishing roller 
kept hot by a simple device, thus allowing the work to be carried 
on without interruption. The construction, as shown in Fig. 297, 
is as follows : In a hollow steel roller about four to six inches 
long and about two and a half inches in diameter fits exactly a piece 
consisting of two cross spokes connected by a shaft projecting on 



TAWIISTG. 663 

both sides. To the spokes is fastened a sheet-iron cylinder of 
the same length as the roller, but about one-half inch less in 
diameter. Upon the perfectly round and polished shaft sits an 
oblong spirit lamp the wick of which can be regulated, and the 




bottom of which, in order to keep the lamp constantly in a ver- 
tical position, is weighted with lead. A handle with branches for 
the reception of the ends of the shaft and with an upholstered 
crutch serves for guiding the apparatus. For working with 
such a polishing roller it is only necessary to regulate the flame 
of the spirit lamp so as to heat the roll adequately, the remain- 
ing work being the same as with an ordinary roller. 

Instead of polishing rollers ordinary flat irons are employed 
in many small work-shops, the manner of using them requiring 
of course no further comment. As regards the construction of 
more complicated polishing and finishing machines, the use of 
which, compared with their cheapness, offers great advantages, 
we must refer the reader to the respective patents. 

For inferior qualities of leather, especially such as are obtained 
from the skins of diseased animals, the operation of smoothing 
is frequently preceded by that of glazing, by spreading the 
leather upon a smooth table and applying a thin coat of white 
of egg, gum, or mucilage of gum tragacanth. In using white of 
egg for the purpose it is best to beat it first to a froth in the 
same manner as cooks do, and then add, with constant stirring, 
double its weight of water. By allowing the whole to stand in 



664 THE MANUFACTURE OF LEATHER. 

a warm place for about twelve hours, an available solution of 
white of egg is obtained, which is applied with a soft brush, or, 
still better, a small clean sponge. The best proportion for gum 
solution is 1 part of gum to 8 to 10 of water. The leather after 
glazing is dried and finally polished with the smoothing roller. 
Leather thus treated is known as glazed or ylace leather. 

The above described method of preparing French or Erlanger 
leather, although the most common, is by no means the only 
one employed. Many methods differ, in fact, essentially from 
the one described, and, although they are, generally speaking, 
antiquated, and offer no material advantage, we will give a short 
description of them. 

Aikins's method of working lamb-skins into glove leather is, 
according to Dr. 0. H. Schmidt, as follows : — ■ 

After soaking the skins in water for some time to free them 
from adhering dirt, blood, etc., they are laid upon a beam cov- 
ered with strong leather, and worked with the dull edge of a 
segmental scraping knife. A large number of them are then 
hung in a small narrow room heated by flues, and allowed to 
remain until an incipient putrefaction takes place. This is recog- 
nized by a strong odor of ammonia coming from the room on 
opening the door. The regular course of the putrefying process 
is recognized by a thick slime making its appearance upon the 
surface which loosens the roots of the wool so that it can be 
readily plucked from the pelt. 

The skins are then slimed^ that is, scraped upon the flesh side 
and stripped of the wool. They are then steeped in lime-water 
for a longer or shorter time, according to their condition. By 
this process further putrefaction is arrested and the skins con- 
siderably hardened and thickened. The skins are then worked 
upon the beam to remove the slime separated during liming, 
and cleansed and smoothed. 

These operations require much labor and care. The skin 
must not be injured by too long-continued putrefaction, as this 
would convert it into a non-cohesive pulp. Besides, every par- 
ticle of slime must be removed, as even the smallest remnant 



TAWING. 665 

would unfit the skin for further working and for the reception 
of tlie dye. 

The skins are next placed in a vat filled with bran and water, 
where they remain for a time in a state of slight fermenta- 
tion. The hardening and thickening produced by the lime are 
then removed by working the skins upon the beam and scrap- 
ing them soft, by which the skin is actually converted into a 
thin, ductile, white membrane suitable for the succeeding opera- 
tions. 

The manner of treating chamois and goat-skins is nearly the 
same, except that the hair having no other value than for 
plasterer's use, the skins are limed before removing the hair. 
Chamois and goat-skins require, besides, a longer time for 
tawing. 

When taken from the bran steep, the skins to be tawed white 
are put into a bath composed, for 120 skins of medium size, of 
a solution of about 8^ pounds of alum and 4:J pounds of common 
salt in warm water, where they remain until they have absorbed 
a sufficient quantity of the liquor. This operation re-imparts to 
the skins a certain degree of thickness and tenacity. 

When taken from the ivhite hath, the skins, after washing in 
water, are allowed to ferment in a bran steep for some time in 
order to extract a considerable portion of the alum and salt and 
reduce the thickening acquired in the white bath. The skins 
are next dried by stretching them on hooks in an airy room in 
the centre of which stands a stove. When dry they will be 
found converted into a tough, flexible, and nearly white leather. 
To glaze the latter and remove any remaining roughness, it is 
again soaked in water, losing an additional portion of salt by 
the process. The skins are then placed in yelk of egg com- 
pounded with water in a wide vat and\rodden until they have 
gradually absorbed all the egg substance and the supernatant 
fluid is entirely clear. They are then dried in the air and pol- 
ished with a flat iron. 

As will be seen, the principal difference between this and the 
other method is that the tawing is effected with alum and com- 
mon salt alone, while the treatment with yelk of egg, to which 
in this case no flour is added, is executed after the skins are 



666 THE MANUFACTURE OF LEATHER. 

tawed. "We doubt if this modification offers such considerable 
advantages as would justify the increased expense of labor and 
time. Another remarkable difference is that Aikins washes 
the skins after tawing in the white bath, and places them in a 
bath similar to the bran steep, in which they have to pass 
through a short fermentation. This treatment, the consequence 
of which, besides the reintroduction of raising, must be a retro- 
gression in tawing, produces no doubt a tough leather, but 
leaves much to be desired as regards softness and suppleness. 
The method of depilating lamb-skins, the wool of which is to be 
utilized, used by Aikins, is nearly the same as the sweating 
process previously described, and requires no further comment. 
Watts's method of working the skins of lambs, goats, and dogs 
into glove leather differs from the ordinary process only in the 
separation of the treatment in the tawing liquor from that in 
the yelk of egg. 

Schmidt describes this process as follows : — 
Soak the skins in clear water for 24 hours, then place them 
upon the beam flesh side up, and remove the fibres with the 
fleshing knife. Eeplace the skins in water, best in the same 
previously used, for 12 hours. Then scrape again with the 
fleshing knife, and stretch them in a loft or room until a slimy 
substance appears upon the flesh side, which remove with the 
knife. Then suspend the skins in the sweating-room until the 
wool can be readily plucked from the pelt, and when this state 
is reached, place the skins upon the beam and remove the wool 
in the ordinary manner. 

The depilated skins, after soaking in water for 5 to 6 hours, 
are dried and again placed upon the beam and scraped on the 
flesh side to remove all membranous substance, the neck and 
leg pieces being cut off at the same time. 

The skins are next replaced in clear water for 5 to 6 hours to 
soften any dirt adhering to them, and then dried by placing 
them in a wicker basket for about half an hour. When dry 
they are placed in the warm alum bath ; but in case they are to 
be colored it must be done before placing them in the alum 
bath. 

For 120 skins of medium size a solution of 12 ounces of ordi- 



TAWING. 667 

narj alum in about a bucketful of water is required. To dis- 
solve the alum completely it is necessary to bring tiie liquor to 
the boiling-point, the temperature being afterwards reduced by 
pouring about one-half of the boiling liquor into the same 
quantity of cold water. 

In the alum liquor the skins are kneaded with the hand for 
about a quarter of an hour. The remaining portion of the 
liquor is then added, and, after working the skins for a quarter 
of an hour longer, they are dried in a wicker basket. 

When dry a workman treads the skins for a quarter of an 
hour in a blood-warm liquor, composed, for 120 goat-skins, of 
the yelks of 40 hen eggs and half a bucketful of water, and for 
120 lamb-skins of the yelks of 30 hen eggs and the same quan- 
tity of water. After thoroughly absorbing the liquor the skins 
are stretched in the air to dry. When dry they are placed in a 
damp cellar for eight to ten hours. Finishing is effected in the 
"usual manner. 

We will finally describe M. Main's, of Niort (France), process 
of finishing alumed leather, which gives a very soft and ductile 
product. It is adapted to every variety of leather, provided it 
is strong enough, and, what is still more important, of a uniform 
thickness ; but it may be especially recommended for leather 
not readily salable in consequence of the grain being not clean, 
or, at least, injured or spotted. 

The modus operandi of the process is as follows : — 

Place the closest and strongest alumed skins in warm water, 
and, after soaking thoroughly, put them upon a smooth beam 
covered with thoroughly washed, unfinished calf, sheep, or 
buck-skin. Then scrape the alumed sheep-skin or goat-skin as 
strongly as you would buck-skin or oil-tawed sheep- skin, con- 
tinuing until all the membranous portions are removed. 

The workman, after passing the tool over the entire surface, 
suspends the skin by the hind legs to two iron hooks for dry- 
ing, or stretches it on a string. When dry, the skin is fulled 
and treated in the usual manner. 

In case a skin becomes drawn together by too quick drying 
it is only necessary to moisten it slightly. 

The skins are then turned over to the pumicer, who, after 



668 THE MANUFACTURE OF LEATHER. 

placing them upon the beam, proceeds to rub the places from 
which the grain has been removed with pumice-stone. 

Skins which are to remain white for a time, and to be colored 
afterwards, are treated by applying very fine sea-sand, and rub- 
bing quickly and forcibly up and down, or backward and for- 
ward, with the pumice-stone held in the right hand, while the 
left hand grasps one end of the skin. 

For leather, which is to be of a pale-yellow color, a stone is 
prepared by pulverizing 6 parts of Mendon white (a variety of 
chalk) and 2 parts of yellow ochre. The ingredients are mixed, 
and, after moistening and kneading, the paste is moulded, and 
the resulting stone used for rubbing the places from which the 
grain has been removed. The workman presses the pumice- 
stone strongly upon the surface of the skin, and rubs as quickly 
as possible, adding occasionally some fine sand, and continuing 
the rubbing as long as for skins which are to remain white or 
are to be colored afterwards. 

By thorough pumicing the fineness of the skin imparted by 
the above treatment, and removal of the grain is augmented. 
It is rendered still finer and smoother by smoothing with a flat- 
iron after stretching, and can then be used for the best quality 
of gloves. 

Danish Glove Leather. 

In order to prepare supple Danish glove leather the method 
of finishing glace leather can be combined with the process of 
preparing tanned leather. By treating the skins with weak tan- 
liquors the desired color is obtained, though a complete tan- 
ning is not effected. The skins are then scraped upon the flesh 
side, and treated with a tawing paste composed, for 144 goat- 
skins, of 4J pounds of alum, 2 J pounds of common salt, 13^ pounds 
of fine rye flour, and the j^'elks of 300 eggs, to which is added 
some birch-tar oil to imitate the weak odor of Eussia leather, 
characteristic of Swedish or Danish leather. The skins are 
worked with the paste in the same manner as already described, 
and, after drying, placed in a damp cellar for some time, and 
finally rubbed upon the grain side with a woollen rag dipped in 



TAWING. 669 

amianthus or tuffaceous limestone. If sucli Danish leather is 
to be used for gloves it is absolutely necessary to have the flesh 
side, which is worn outside, as smooth and uniform as possible. 
To effect this the skins, after scraping upon the beam, are 
rubbed in the above-described manner with pumice-stone, to 
which it is advantageous to add some fine sea sand. After rub- 
bing the surface as smooth as possible, the skins are finished 
by treating with a polishing roller or flat iron. 

Jennings's Method of Tawing. 

Jennings, in 1861, obtained a patent in England for a spe- 
cial method of preparing white leather, which differs not only 
from the ordinary method as regards the nature of the taw- 
ing substances used, but also as to the quality of the leather 
produced. The preparatory labors, such as soaking, rinsing, 
liming, and depilating, and working upon the beam, are precisely 
the same as in the ordinary method, though we will remark 
here that depilating is best effected by previous liming. If it 
is to be accomplished by the sweating process, it will be neces- 
sary to treat the skins afterwards with weak lime-water. To 
accomplish a loosening of the tissue and saponification of the 
fat, an after-liming for 24 hours will, on an average, be necessary. 
The process is available for all kinds of skins, though it is 
especially adapted for heavy ones. 

After liming and washing the skins are worked upon the 
beam to assist the removal of the lime soaps, and then placed in 
an acid bath composed of a mixture of 98 parts of pure water 
and 2 parts of concentrated hydrochloric acid where they 
remain, with frequent careful stirring, until the removal of the 
lime and raising of the tissue produced at the same time by the 
action of the acid, are as completely effected as possible, two or 
three hours being as a general rule required for the purpose. 
The skins are then taken from the bath, and, after draining off, 
subjected immediately to the tawing process. This is effected 
by placing the skins in two different tawing fluids prepared in 
two separate pits or vats. One fluid consists of a cold saturated 
solution of alum in water with an addition of about 2 per cent. 



670 THE MANUFACTUEE OF LEATHER. 

of sulphuric acid, and the other of a cold saturated solution of 
crystallized soda with an addition of about 5 per cent, of dry 
sodium tungstate. The preparation of these fluids is readily 
accomplished. 

For the first pour cold water, not sufficient to dissolve it, over 
a large quantity of crystallized alum in a vat, and allow it to 
stand with frequent stirring until the quantity of alum not dis- 
solved no longer perceptibly decreases. Then run the obtained 
solution into the tawing pit or vat, and add, with thorough 
stirring, the corresponding quantity of acid. 

Tlie other fluid is prepared in the same manner, and the 
corresponding quantity of sodium tungstate previously dissolved 
in the necessary quantity of water is added.^ 

After filling the pits at least half full with the respective 
fluids, the skins are first placed in the one containing the alum 
solution. To facilitate the immersion of the skins and their 
removal from the pit Jennings makes use of a very convenient 
method. He employs for the purpose a perforated wooden frame 
large enough to spread upon it a large skin. Upon this frame 
he spreads out a skin, places upon this a hurdle of pealed osiers, 
upon this a skin, and so on until 10 to 12 skins are placed upon 
each other separated by hurdles. A hurdle is placed on top 
and fastened to the frame with cords so that the whole forms a 
bundle. By means of handles the bundle is then immersed in 
the pit so that it is entirely covered by the fluid. 

After remaining in the alum solution for six hours, during 
which time the fluid washing around the skins is renewed 2 or 
3 times by repeated lifting and replacing the bundle, the skins 
are taken out, and, after draining off over the pit, placed in the one 
containing the soda solution, where they remain for 5 hours, and, 
after draining off, are replaced in the first pit. This alternate 
moving from one pit into the other is repeated until the skins 
are converted into leather, which is recognized by the opaque- 
ness of the cut surface and the fibrous structure. The time 

• In case determined proportions by weight are preferred it is necessary to 
tise for the alum solution 100 parts of water and 9^ parts of crystallized alum, 
and for the soda solution 100 parts of water and 16^ parts of crystallized soda. 



TAWING. 671 

required for the operation depends of course on the size and 
thickness of the skins, but can be hastened somewhat by using 
the solutions lukewarm, say at about 96° to 100° F., which is 
recommended and necessary in winter. To increase the pro- 
ducing capacity it is of course advantageous to work with at 
least two frames, so that, while one bundle is in the one solu- 
tion, the other is treated in the second. 

After the skins are taken from the tawing fluids they are first 
placed in a bath of sodium tungstate and finally in one of soap. 
The first is prepared by dissolving the sodium tungstate in a 
sufficient quantity of water, allowing the solution to settle and 
pouring off' the supernatant clear fluid from the sediment. The 
skins remain in this solution, with frequent stirring, until they 
are completely saturated, the process requiring as a rule several 
hours. They are then taken out, and, after draining off", placed 
in the soap bath prepared by dissolving 15 to 20 parts of ordi- 
nary white soap in 100 parts of water. The skins remain in 
this solution until they have absorbed almost all the soap, which 
is recognized by the fluid feeling no longer slipperj', and ceas- 
ing to foam. The process can be considerably hastened by fre- 
quently working the skins in the bath. The final operation is 
rinsing the skins to free them from an excess of salts. As sim- 
ple rinsing is not sufficient for this purpose, the skins are soaked 
for 24 hours in water frequently changed, and after a final rins- 
ing in clean water, dried, and submitted to the finishing pro- 
cess. The color of leather thus prepared being not entirely 
white, it is more advantageous to use it for preparing colored 
varieties. If it is to be brought into commerce as natural 
leather, it is best to give it the appearance of tanned leather by 
placing it before drying in weak tan-liquor for 15 to 24: hours, 
according to the thickness of the skins. After the leather is 
thoroughly permeated with the liquor, which can be more 
readily effected by the use of pressure, it is dried and finished. 
Where a higher degree of softness and suppleness is desired, the 
finished leather can of course be greased, the process being the 
same as the one described for the Hungarian method of tawing. 
For obtaining fine and very white leather by Jennings's method, 
the use of the above tawing fluids alone is not sufficient. To 



672 THE MANUFACTUEE OP LEATHER. 

give the tawed leather a proper degree of whiteness. Jennings 
recommends dissolving 5 per cent, of zinc filings in the acidu- 
lated alum solution, for which might perhaps be substituted a 
correspondingly larger quantity of oxide of zinc or sulphate of 
zinc. 

As regards the theory of this method of tawing we may make 
the following general remarks : It is, of course, self-evident that 
the action of the alum upon the fibres of the skin tissue does 
not materially differ from any other method where alum is used 
for tawing. But what is the object of the succeeding treatment 
with soda solution ? To understand this thoroughly we must 
consider the behavior of alum towards soda. Alum, ^. e., alu- 
minium sulphate on meeting soda, i. e., sodium sulphate, is 
decomposed and soluble sodium and potassium sulphates are 
formed on the one hand, and on the other insoluble aluminium 
hydrate. There can be no doubt that by the action of the soda 
solution upon the skin the fibres of which have absorbed a certain 
quantity of alum by the treatment in the alum bath, the same 
process of decomposition is introduced, and that the particles of 
alum present in the tissue are, on the one hand, converted into 
sodium and potassium sulphates, which being easily soluble are 
absorbed by the surrounding liquid, and, on the other hand, into 
aluminium hydrate which, being insoluble, will remain in the 
place formerly occupied by the particles of alum. In this man- 
ner the tissue of the skin will, by the repeated alternate im- 
mersion in the alum and soda baths, be gradually saturated 
with aluminium hydrate until finally not only the separate' 
fibres will be coated with the aluminium combination, but the 
interspaces will also be filled with it. The sodium tungstate, 
which under certain conditions can effect a sort of tawing, 
though not a complete one, might, as far as the matter can be 
judged from a theoretical standpoint, play only a subordinate 
role, and is very likely added to assist the tawing and perhaps 
make it more constant. A skin the tissues of which are filled 
with aluminium hydrate is no doubt genuine leather, but it lacks 
properties demanded of good leather, which must principally 
possess a certain degree of softness and suppleness. Dry alumi- 
nium hydrate being earthy and rough, its presence must oppose 



TAWING. 673 

a considerable resistance by friction to ever}'- motion of the tis- 
sue fibres. To obviate this evil, and to decrease as much as 
possible the friction of the separate parts, the skins are treated 
in the soap bath, by the action of which upon the aluminium 
hydrate an alumina soap is formed, which consists of a slippery 
mass offering but little resistance to the shifting and moving of 
the tissue fibres enveloped by it. The treatment in the soap 
bath could thus only be omitted at the expense of softness and 
suppleness, and its continuation is therefore advisable. 

The object of adding zinc filings, or a soluble zinc salt, to 
obtain a higher degree of whiteness, is easily explained by the 
circumstance that by the action of soda solution upon soluble 
zinc salt, carbonate of zinc, i. e., a body of a pure white and 
great power of covering is formed, which, when deposited in 
the tissue alongside of the aluminium hydrate, imparts to it 
its whiteness. It is, therefore, of no consequence whether zinc 
shavings are added to the acidulated alum solution or a soluble 
zinc salt, for instance, sulphate of zinc ; in fact the latter is pre- 
ferable, as in case sufficient time had not been allowed for the 
zinc shavings to dissolve the skins coming from the soda solu- 
tion containing tungstic acid might assume a blue coloring, 
which, though only transient, would disturb the regular course 
of the work. We would finallv remark that the tawina; effected 
by Jennings's method is more constant than that by the ordi- 
nary process, and the leatlier resists the action of water much 
better. The cause of this phenomenon must be found in the 
fact that by Jennings's method the fibres are enveloped by an 
aluminium combination almost insoluble in water, while in the 
■ ordinary method the tawing is effected by the absorption of a 
more or less soluble combination. 

Defects of Alumed Varieties of Leather. 

The defects are either natural ones, or originate from storing 
or the manner of working. 

Perforated skins are frequentl}^ found, the holes in most cases 
being made by the maggot of the large blue fly found so fre- 
quently in butcher shops, feeding upon the particles of fat and 

43 



674 THE MANUFACTUEE OF LEATHEE. 

flesli adhering to the stripped skin. The fly frequently deposits 
its eggs in the folds of the still moist skin, and the maggots on 
making their appearance and finding no other food attack the 
leather itself. The skins should therefore be stretched and 
dried immediately after stripping them from the animals. 

Lambs, and sheep still more so, are subject to diseases leaving 
their effects upon the skins, as for instance the small hard places, 
about the size of a pea, occurring principally on the back and 
neck, which must be classed among the worse defects, as they 
do not take the color. These lumps originate no doubt from 
chicken-pox, which frequently attacks entire flocks. 

Another similar disease produces smaller spots, and frequently 
only depressions, so that the skins can be at least used upon the 
flesh side. Such places are frequently found in goat-skins 
brought from hot countries. 

Another injury to the skin, chiefly found on the sides and 
upon the grain side, originates from not keeping the animals 
clean. By the dung, moistened by the urine, adhering too long 
to the animal, not only is the wool injured but the skin also. 
Such skins can only be used for dark colors and frequently 
only for black. 

Marks of varying shapes and of a wine-lees color, which do 
not disappear in tawing, are called hlood stains. They are very 
likely a kind of liver spot or mole. Actual blood stains are 
also found on the edges of large sheep-skins. They are caused 
by the blood adhering to the skins decomposing and producing 
indelible stains. 

The wool, or the hair of the skins of goats and lambs, is 
either white or reddish, or black, and sometimes spotted. The 
white skins, which are the most frequent, have after tawing a 
dull white color, while the black ones are more beautiful, but 
have a bluish-white color. Spotted skins are also more or less 
irregularly spotted so that they can never be used for white 
gloves, and frequently not for even light colored ones. 

Skins, the grain of which is only slightly connected with the 
grain side, and the tissue of which is loose and hollow and can be 
easily torn, are called swelled or distended. Such skins are only 
obtained from diseased lambs or sheep, or from flocks fed upon 



TAWING. 675 

fat pastures. They are only used where more regard is paid 
to cheapness than to good quality. In reliable factories they 
are not worked, at least not upon the grain side. 

Skins of animals which have died of a kind of wasting dis- 
ease, are called dry skins. They are generally thin, without 
elasticity, have large open pores, and cannot be improved even 
by the most careful working. They are unfit for gloves. 

It is frequently found that the grain side becomes partly 
detached from the skin. This is caused by the skins becoming- 
heated while stored. This evil can be prevented by stretching 
and thorough drying of the skins before storing them away. 

Skins attacked by certain kinds of moths show, after tawing, 
the course the moth has taken in gnawing off the wool, while 
the small larvge of the genuine moth do not penetrate to the 
skin. The marks left upon the skin are not produced, as is 
erroneously supposed, by the bite of the insect, but by an acrid 
fluid running from the mouth of the insect while cutting the 
wool, and which very likely promotes the separation of the wool 
from the skin. Skins furrowed in the above manner were 
formerly frequently found in workshops where the wool was 
removed by means of a sharp slate, but scarcely ever occur 
since the general introduction of the scraping-knife for depi- 
lating. 

We have already spoken of the injury to which the skins are 
liable in branning in case the fermentation is too strong. 

It is frequently the case that small fissures or similar injuries 
are found upon the grain side, which are partly caused by the 
butcher inflating the skins and partly by the workmen, while 
tawing the skins, especially in depilating and scraping. The 
skins of young animals fed upon moist pastures^ as for instance 
the goats in the vicinity of Paris, require the most careful treat- 
ment in tawing as well as in coloring, to prevent them from 
receiving such injuries during the course of the work. 

The best skins will sometimes turn out hard if not thoroughly 
worked by the tawer, and especially if too little tawing paste 
has been applied. By treating such skins before tawing in the 
manner mentioned later on, they will be rendered sufficientl}'' 
soft. 



676 THE MANUFACTURE OF LEATHER. 

Gases being developed in consequence of a fermenting pro- 
cess taking place in branning, it occurs occasionally that the 
gases developed by the fluid absorbed by the skins, cauDot find 
a suitable way of escape and are collected between the epider- 
mis and the true leather skin. By an increase of gas the re- 
spective portion of the skin is distended and a detaching of the 
epidermis from the other skin tissue is the result. Such skins 
have the appearance in a moist state of being covered with 
blisters. Though these blisters disappear in drying, the skins 
never acquire a perfectly smooth surface or, in short, a clean 
grain. 

The best way of preventing this evil is not to use the bran 
steep too strong, and avoid excessive fermentation by keeping 
up a moderate temperature, and also by frequent handling of 
tbe skins while in the bran steep. In case the detached skin is 
perfectly clean and free from other parts of the skin it is in 
much demand by manufacturers of artificial flowers, who use it 
especially for imitating orange blossom. 

The ordinary reddish bran stains are caused by the use of bad 
or impure bran. In dyeing such skins, the stained places form 
small grayish spots. These spots, which are also called rust 
stains, may be formed by filings dropping upon the skins in 
sharpening the stretching iron. To avoid them the workmen 
should never be allowed to sharpen their tools in the vicinity 
where skins are piled up. The appearance of similar grayish 
spots after coloring the skins is due to another cause. Portions 
of the tissue of skins stored in a damp place undergo decompo- 
sition, the formation of mould on the surface of such places 
being observed at the same time. The appearance of the spots 
is caused by the products of this process of decomposition. 
The spots are readilj detected by holding the skin,- before 
cleansing it for .dyeing, against the light. The skin hassuifered 
injury when blackish stains are observed in the interior. Such 
skins can only be utilized for verj'- dark leather. 

A very frequently occurring defect is technically called shading. 
It is YGxy plainly noticed especially in colored leather. One 
cause of this defect is that not sufficient care has been used in 
hanging up the skins to dry. By throwing the leather over the 



TAwma. 677 

pole more tawing paste collects generally on those places resting 
immediately upon the pole, and the whole width of the leather 
shows a streak corresponding to the greater collection of tawing 
paste, which indicates a somewhat differently constituted sub- 
stance from the remainder. This difterence is not noticed in 
white leather, but in dyeing it will appear plainly, as such places 
will show a more intense coloring than the rest of the skin. This 
defect is also frequently caused by stretching the skins taken 
from the tawing paste, and can scarcely be avoided where the 
stretching is executed by drawing the leather back and forward 
over a wooden pole. By the pressure exerted upon the leather 
in pressing it against the wooden pole, a kind of streak or 
several streaks are produced if the work is not done uniformly, 
which after dyeing show a darker coloring. This evil can be 
avoided, on the one hand, by not drying them upon poles, but 
suspending them, as previously mentioned, their entire length, 
and, on the other hand, by stretching them only with the hands 
without the use of a wooden pole, or, if the latter has to be em- 
ployed^ by being careful to stretch the leather uniformly and 
drawing it over the pole not only crosswise, but also lengthwise 
and repeatedly in different directions. Another cause of shad- 
ing is subjecting the skins to too strong a lime-bath, or it may 
be produced by the grain of the skins in the lime-vat being 
partly injured or entirely destroyed by the action of the air, in 
consequence of which the finished leather will be without lustre 
and dull. 

The defect of what is called rotten or burned leather was 
formerly attributed to various causes, none of which is however 
correct. Credit is due to Prof. Knapp for having thrown light 
on this subject by a series of interesting experiments. Without 
entering into details, we will only give the conclusions Knapp 
has arrived at as to the cause of the rotteness of leather. There 
is no actual burning, as the fibre of the tissue is not injured or 
destroyed but remains entirely intact. The cause of the defect 
is due to the presence of certain salts enveloping the fibres and 
by forming a brittle coating depriving them of the power of re- 
sisting a tearing force. Knapp compares the condition of such 
fibres with that of the threads forming the wick of a stearine 



678 THE MANUFACTURE OF LEATHER. 

candle which, though in a normal state, are broken in breaking 
the candle, the presence of a brittle substance enveloping them 
weakening their power of resistance. The cause of the rotten- 
ness of the leather must, according to this, be due to the fibres 
becoming, in the course of the tawing process, enveloped with a 
more or less brittle substance or at least a hard one, and the 
evil could be entirely avoided by removing such coating or pre- 
venting its formation. And this is actually the case. Knapp 
proves unequivocally that the formation of such brittle sub- 
stances is due to a remnant of lime either by itself or in combi- 
nation with the fibres, which by the succeeding action of the 
alum liquor is converted into calcium sulphate, the latter being 
deposited in the form of brittle crystalline masses upon the 
surface of the fibres. The most suitable means of prevention 
would therefore be to use the greatest care in removing the 
lime from the skins, which can be best eft'ected by thorough 
and repeated stretching of the depilated skins and by subsequent 
use of the acid bran steep, and, still better, by hydrochloric acid 
baths. Skins containing too much lime are improved by treat- 
ing them with a dilute solution of sodium phosphate, or, as 
Knapp recommends, with a soap solution. These agents do 
not remove the lime from the tissue, but produce the desired 
efi'ect by forming combinations with the lime not inclined to 
form such crystalline envelopes upon the fibres. A similar 
effect, although only within certain limits, is produced by the 
use of a bate of dog excrements, and also by such substances as 
flour and yelk of egg employed in the French mode of tawing, 
this being the reason why rotten leather will result more seldom 
by this process than in the ordinary method. Oiled leather also 
shows this defect very seldom, in fact, apparently rotten leather 
can frequently be restored by oiling, as the fat penetrating the 
tissue forces its way also between the crystals of the calcium 
sulphate enveloping the fibres, restoring, at least partly, their 
flexibility. 

We would finally draw the attention of our readers to a defect 
occasionally observed in colored leather and consisting of white 
spots which will take no color whatever. The occurrence of 
these spots has thus far not been satisfactorily explained nor a 



TAWING. 679 

means found to prevent tliera, and it is simply a supposition to 
saj that their production might be due to small pieces of egg 
shell whicli adhere to the skins in treading them in the tawing 
paste. 



Manufacture of Oil or Chamois Leather. 

Oil or chamois leather has various employments, and under- 
goes a treatment which imparts to it a softness, suppleness, and 
woolly nature resembling that of woollen goods, and the property 
not possessed by any other variety of leather, of standing wash- 
ing without losing any of its good qualities. For this reason, 
it is also frequently called loash leather. 

As, on account of its denser tissue, the upper layer of the 
corium does not possess the same stretching capacity as the 
lower, the grain is generally entirely removed, especially in 
thick skins, so as to give both sides the same appearance. For 
making leather capable of standing washing, it is necessary that 
the fibre should not lose its tawing when placed in water, nor 
shrink to a horny mass in drying. The fibre acquires this 
property by treating the properly prepared skins with oils and 
fat. The tawing is, however, not efi'ected by the pure unal- 
tered fat, but is partly due to other factors the importance of 
which must not be underrated. Among the principal of these, we 
must class the action of heat and air, and especially the oxygen 
of the latter by the action of which the fats absorbed by the skin 
tissue undergo an alteration the products of which must be con- 
sidered as the actual tawing agents. 

The products formed by the chemical alteration of the fat not 
only unite the fibres so far as to give them all the characteristics 
of being thoroughly tawed, but prevent the fat contained in the 
leather from being detected by any external mai'ks. But 
although, the percentage of fat deprives more than any other 
means the fibres of the capacity of shrinking and sticking to- 
gether, it would be erroneous to suppose that it prevents water 
from penetrating the leather. 

This branch of the trade takes its name from the skins of the 
chamois, but, although the term is still retained, those of sheep, 



680 THE MANUFACTURE OF LEATHER. 

deer, lambs, and goats, and even ox-hides and calf-skins, are now 
converted into it. The product obtained from the latter is 
almost exclusively used for military equipments, such as belts, 
etc., while the leather produced from the first is worked into 
pantaloons, bags, bandages, gloves, etc., though we would here 
remark that of late the use of chamois leather for these purposes 
has considerably decreased. 

The manufacture of chamois leather has undergone but little 
change in the course of time, nearly the same process being in 
use at present as in the last century. The operations may be 
divided under the following principal heads: 1. Soaking and 
rinsing. 2. Liuiing, depilating, and frizzing (removing the 
grain). 3. First liming of the frizzed skins. 4. Stretching and 
scraping. 5. Second liming of the frizzed skins. 6, Branning. 
7. Squeezing or pressing. 8. Fulling in the oil. 9. Dressing 
and finishing. 

Soaking and rinsing and liming to prepare the skins for 
depilating being the same as used for ordinary alumed leather, 
require no further description. 

After thorough liming the skins are ready for 

Depilation and Frizzing. 

These operations differ materially from the method employed 
for alumed leather. The grain of the skin being, as previously 
mentioned, the densest part, is not adapted for such a high 
degree of softness and suppleness as is demanded in chamois 
leather, and besides prevents, on account of its density, a ready 
penetration of the fat. For the production of good wash leather 
it becomes therefore necessary to remove the grain, though it is 
done at the expense of lustre and smoothness. In depilating 
skins intended for chamois leather, it is therefore not necessary 
to be careful of the grain except with very weak skins of young 
animals, the solidity of which would be injured by the removal of 
the grain, and in case the wool is to be utilized for other purposes, 
as wool removed simultaneously with the grain has no value. 
In all other cases the depilation and frizzing are accomplished 
at one operation, i. e., the hair or wool and the portion of the 
skin in which they are imbedded are removed together, the 



TAWI^STG. 681 

workman using for the purpose a sharp scraping-knife sirnilar 
to the one employed for skins intended for alumed leather. 
The treatment with the scraping-knife being generally not suffi- 
cient for complete frizzing, the remaining portions of the grain 
are removed with another sharp knife. After frizzing and 
rinsing, or without the latter, the skins are subjected to the 

First Liming, 

For this purpose they are placed in an ordinary lime-vat and 
subjected to the action of lime-water for 12 to 48 hours accord- 
ing to their size and thickness. The object of this treatment, 
which is equivalent to the raising of skins intended for alumed 
leather, is besides the saponification of the fat constituents of the 
skin, to loosen the skin tissue for the succeeding treatment. 
The next operation is 

Stretching and Scraping upon the Flesh Side and partly upon the 

Grain Side. 

This is accomplished upon the beam with a scraping-knife, 
the object being to free the flesh side from adhering particles of 
flesh and fat, and the substance of the tissue from the lye and 
lime-soaps which have been formed, thus preparing the skin 
tissue for the absorption of fresh lime-water in the 

Second Liming. 

This is generally accomplished by placing the skins for 24 to 
48 hours in a vat charged with fresh lime-water prepared in the 
ordinary manner for raising skins. By this treatment the skins 
acquire the necessary degree of softness and sponginess required 
for the succeeding operations. 

After removal from the lime-vat, the skins are thoroughly 
rinsed in lukewarm water in order to free them from the greater 
portion of the adhering lime, and are then subjected to 

Branning. 

For this purpose the skins are placed in a bran steep acidu- 
lated by standing several days, for the preparation of which the 
same proportions in quantities are used as given for alumed 



682 THE MANUFACTUKE OF LEATHER. 

skins. The acid steep should be warmed before pouring it over 
the skins in the vat. After a partial permeation of the skins, 
which is generally effected in a few hours, during which time 
they should be kept immersed by proper weights, a complete 
saturation is accomplished by treading them in a vat, in order 
to make the action of the steep uniform upon all parts of the 
skin tissue, and to accomplish a complete removal of lime from 
the fibres, which is the principal object of the sour steep. In 
place of treading, the object may be effected by pounding the 
skins in a low wooden vat or special fulling trough with a 
round wooden mallet. The pounding is continued, with an 
occasional addition of bran steep, until the skins have acquired 
a uniform milk-white appearance, and show, when held against 
the light, no dark spots, this being generally accomplished in 
winter in 2 days, and in summer in 12 hours. The skins are 
then squeezed or pressed in order to remove as much water as 
possible, this operation requiring no further description, as it 
does not differ from the ordinary method pursued in tawing. 
We will only mention that it is advantageous to use a wooden 
instrument in place of the usual iron one, especially for leather 
to be colored afterwards, in order to avoid spotting, frequently 
brought about by the skins taken from the bran steep coming 
in contact with iron instruments. After thorough wringing 
and swinging in the air the skins are again fulled and while 
still moist immediately oiled. 

Fulling in the Oil. 

Fish oil, obtained from seals, whales, sturgeons, dolphins, and 
herring, is preferred for this purpose, partly on account of being 
cheaper and partly because other fats do not give as good a pro- 
duct. The only oil worth mentioning besides the above is olive 
oil, while linseed oil, rape-seed oil, and poppy-seed oil must be 
designated as absolutely worthless, as they furnish a poor pro- 
duct even when used as an addition to fish oil. Oil of juniper 
deserves, according to Schmidt, consideration as the volatile oils 
free from oxygen dissolve the fat of the connective tissue and 
are oxidized much more quickly than fish oil and converted into 
soft resins, which form with the fats and the alkalies, a more solid 



TAWING. 683 

resin soap enveloping the connective tissue fibres, than is the 
case with fish oil. But the introduction of this material has 
found but a limited use as might be expected from the material 
difference existing between this and other oils. The operation 
of tawing consists in spreading about 12 dozen skins, or as many 
as are required to fill the trough of the fulling mill, grain side 
up, upon a table, and after sprinkling upon them oil, distributing 
it uniformly over the surface with the palm of the hand. The 
skins are then rolled up in bundles of four, and subjected to the 
action of the fulling mill. This latter for this class of leather 
manufacture is generally driven by horse-power, and is the same 
as an ordinary cloth fulling mill. It has two hammers and two 
troughs capable of holding a gross of skins or more. The ham- 
mers give 15 or 16 blows per minute. 

The first fulling is continued for a period varying from 2 to 
3 hours, the time depending partly on the temperature of the 
air and the more or less porous condition of the skins. They 
are then taken out, and after swinging in the air in order to 
unfold them, suspended to cords in the open air to cool off' from 
the heating consequent on fulling, and to allow of a better pene- 
tration of the oil by a partial evaporation of moisture. After 
half an hour to an hour the skins, after rolling them again into 
bundles, are fulled without oil for 1 or 2 hours, suspended in the 
air, oiled, again fulled, suspended in the air, fulled without oil, and 
so on, the process being repeated until the skins have been hung 
6 to 8 times in the air, being fulled each time and receiving oil 
3 to 4 times or oftener for poor skins. 

Fulling is the most important and at the same time delicate 
operation in oil-tawing, the smoothness and softness of chamois 
leather, so much admired, being entirely due to it. Formerly 
a fulling stock descending perpendicularly upon the skins was 
used, but more recent constructions are provided with a kind 
of hammer, the arrangement of which will be more plainly seen 
from the illustrations in Chapter XIV. 

The skins will be sufficiently oiled when a smell of mustard 
takes the place of that of flesh. The skins should gradually lose 
their water by repeated suspensions in the air, since the oil pene- 
trates more easily in the degree in which the water evaporates, 



684 THE MANUFACTURE OF LEATHER. 

and thoroughly dry skin absorbs the oil with great difficulty and 
requires more frequently repeated fulling. The skins remain 
generally suspended until the surface appears dry. It is best 
to hang them in the open air or in case the weather is unfavor- 
able in an airy loft. Towards the end of the operation, when the 
skins have lost the greater portion of water, they are suspended, 
in damp weather, in a heated room. Chamois skins are given 
12 fullings, other skins proportionably less. A dozen buck- 
skins absorb about 18 ounces of oil at each oiling, a total of 
about 9 to 10 pounds of oil being required for a dozen steep- 
skins, and about 13 to 13J pounds for a dozen buck-skins. Thus 
far the object of the operations is principally to thoroughly and 
uniformly impregnate the skins with oil, repeated fulling play- 
ing a principal part. By the repeated exposure to the air a 
part of the oil has, however, already undergone a partial altera- 
tion by the action of the oxygen of the air causing the forma- 
tion of various products of oxidation, which chiefly impart to 
the skin the property of leather. But the principal portion of 
the fat is still present in an unaltered state, and fills only 
mechanically the interspaces of the tissue. The object of the 
succeeding operations is to convert the unaltered fat so as to 
adapt it to form an intimate combination with the skin tissue, 
and to bring about a lasting tawing of the skin. This is effected 
by the oxidizing action of the air, best produced by the co-opera- 
tion of a gentle heating ; therefore, by the introduction of what 
has been erroneously called " a fermentation accompanied by 
heat." 

After the last fulling and thorough swinging in the air, the 
skins are piled in a cone-shaped heap upon the floor of a heated 
chamber previously covered with a linen cloth, and allowed to 
rest some time. In some workshops the pile is also covered 
with a linen cloth, though this is not absolutely necessary. In 
cold weather the skins must be heated before piling them up, 
which is effected by suspending them on poles arranged near 
the ceiling of the heating chamber. The interior of the pile 
soon becomes perceptibly heated by the oxidation of the fat 
permeating the skin tissue, which is caused by the admission of 



TAWING. 685 

air, the color of the skins changing gradually into yellow as the 
process of oxidation progresses. 

To obtain a good product the heating of the skins must be 
carefully watched and special precaution taken to avoid over- 
heating of the pile, as otherwise a more or less brittle leather 
would be the result. The temperature of the pile should there- 
fore be examined from time to time by introducing the hand. 
If a considerable heat is felt, the pile, in order to avoid a failure 
of the process, is rapidly torn apart, and a new pile formed as 
quickly as possible to prevent too rapid cooling, by placing the 
skins previously in the interior, on the outside of the pile. 
After allowing the pile to rest for some time, it is again changed 
in a similar manner. This reforming of the pile and subsequent 
resting is repeated until the skins have acquired the right 
shade of color, which, as previously mentioned, takes place in 
consequence of the oxidation of the fat. When the latter pro- 
cess is finished, the skins will no longer become heated to any 
extent, so that the gradual decrease of heat may be considered 
as a sign of the process being finished. After passing 
through the process in the heating chamber the skins, in order 
to furnish available oil leather, must still be subjected to 

Finishing and Dressing. 

The principal object of these operations, besides the other 
mechanical treatment, is the removal of the excess of fat con- 
tained in the tissue. For this purpose the skins are first worked 
with the stretcher and then upon the grain side with a some- 
what dull round knife to remove any grain still remaining. 
This operation is especially required for skins of chamois, deer, 
and goats, whose upper skin is rather thick, and if any of the 
grain remained it would form, after drying, a stiff' and hard 
surface impairing the fine, woolly appearance of the grain side, 
which is worn outside in articles manufactured from the 
leather. 

Although the greater portion of the oil combines in an altered 
state with the skin fibre, the skins contain a considerable quan- 
tity of uncombined oil, which is removed by means of an alka- 
line lye, prepared by dissolving, for 1 dozen sheep-skins, about 



686 THE MANUFACTUEE OF LEATHER. 

1^ pound of potash in warm water, less being required for 
skins previously scraped. The skins are immersed in the bath 
and when thoroughly soaked taken out and wrung, the immer- 
sion and wringing being repeated three or four times until the 
leather is thoroughly cleansed. 

As a considerable amount of potash, which is comparatively 
dear, and frequently contaminated, is used in the manufacture 
of chamois leather, Hermbstaedt proposed, some years since, the 
use of soda as a substitute. This would be still more advanta- 
geous at the present time, since soda is now produced in immense 
quantities and of great purity, and is not only as effective as 
potash, as already proven by Hermbstaedt, but even superior 
to it. The proportions, for 1 dozen skins, are about 1^ pound 
of calcined soda, or 3f pounds of the crystallized article for the 
same number of skins. 

The use of a caustic lye has proved still more advantageous 
than either potash or soda, and experience has shown that only 
half the soda in the form of caustic lye is required as of potash. 
Caustic soda lye is obtained without difficulty by preparing 
first a clear solution of soda in lukewarm water and adding a 
paste of fresh slacked lime made by converting, for every 2| 
pounds of soda to be used, IJ pound of lime into a fine powder 
by pouring as much water over it as it will absorb. The 
powder is stirred into a thick paste with sufficient water, and 
added with vigorous stirring to the previously prepared soda 
solution. After standing for several days during which the 
fluid is frequently stirred, the caustic lye is ready. For use the 
supernatant clear fluid is drawn off. 

By scraping and treating with lye the skins lose about one 
half of the oil originally absorbed. The liquor running off' in 
wringing out the skins treated with lye, which is a solution of 
a soap-like body partly clouded by the mechanical admixture 
of fatty substances, is the so-called degras, an article of consider- 
able value, which should be carefully collected. 

The value of this liquor will be made plain by considering 
that it contains the greater part of the excess of oil from the 
skins and a small part of the products of the oil formed b}^ the 
process of oxidation. This product can in fact be used for 



TAWING. 687 

moistening oil leather to be bleached and, after evaporating the 
water, for oiling other varieties of leather, especially tan- 
leather. 

The liquor can also be used in place of fish oil by neutralizing 
the alkali contained in the soap-like combination in solution, by 
means of hydrochloric or sulphuric acid, and skimming off the 
oil separating on the- surface of the fluid. This is effected by 
diluting the soap-like mass pressed from the skins by fulling 
with a quantity of water and adding with vigorous stirring 
small portions of sulphuric acid until the fluid has acquired an 
acidulous taste. By subsequent heating the fatty substance col- 
lects upon the surface. 

As strong heating takes place on mixing sulphuric acid with 
water, it is advisable to mix the acid drop by drop with 4 to 6 
parts of soft water and add the diluted acid to the liquor. The 
simplest way is to use hydrochloric acid. In treating the liquor 
in the above manner with hydrochloric acid the latter 
combines with the soda or potash into the soap- like substance, 
and separates the pure fat which floats on the surface. The 
separation is promoted by heating the fluid. 

After freeing the skins from the excess of fat they are wrung 
and dried in the air, if the weather permits, or in the drying- 
chamber. When dry the skins are worked 
with the stretcher in order to restore to them =' 

the proper suppleness partly lost in drying. 
Small skins are worked in the usual man- 
ner. 

For strong leather a stretching iron rep- 
resented by Fig. 298 is used. It is fastened 
to the wall of the workshop. The leather 
is scraped lengthwise upon the blunt round 
edge c c?, and in width upon the dull curved 
edge e/, the latter being specially used for 
the thick places in order to make them supple. After this 
operation the skins are finished with the hone to give the 
surface the required uniformity, buck-skin undergoing this 
process on both sides, but sheep-skins on the flesh side only. 




688 THE MANUFACTURE OF LEATHER. 

The leather is finally finished by passing a smoothing iron over 
the honed side in the same manner as in alumed leather. 

Chamois leather is generally of a buff color. To bleach it the 
skins are placed upon the bleaching ground in the sun and 
sprinkled with water, and when dry again sprinkled. When 
half white they are soaked in degras and replaced in the sun. 
In place of degras, soap water prepared from white soap can also 
be used. 

In bleaching the leather from chamois skins intended for 
gloves and that from skins of sheep, goats, and lambs for castor 
gloves, is at the same time pumiced. For this purpose the skins 
are trodden for one hour in a weak solution of potash, composed 
for 12 dozen skins, of 2^ pounds of potash in 79 pounds of water 
of 88° F. They are then wrung out, and after swinging in the 
air, placed upon the bleaching ground for 48 hours. The dry 
skins are then pumiced with white pumice-stone in the same 
manner as given for alumed leather, some fine sand scattered 
between the skin and the stone facilitating the work as the sand 
detaches the fine fibres. After pumicing and smoothing and 
moistening the skins with degras they are spread upon the 
bleaching ground to bleach entirely. When dry they are 
alternately sprinkled with pure water and degras, the latter 
restoring to them their original softness. For leather intended 
for white gloves, the sprinkling is repeated 8 to 10 times, while 
3 to 4 times are sufiicient for leather to be worked into yellow 
or colored gloves. 

The required shade for buff- colored leather intended for panta- 
loons, gloves, etc., is prepared by mixing with water to a thin 
paste the requisite proportions of yellow ochre, whiting, and some 
Dutch or English pink, adding a little starch paste to prevent 
the color from dusting when dry. Apply the color with a stiff 
brush, stretch the skin when dry and finally remove the loose 
dust by vigorous shaking. 

To clean dirty leather proceed in a similar manner. After 
washing with a brush and soap-water mix the above buff color 
with sufficient olive oil to a ball, dilute this with the requisite 
quantity of water and apply with a stiff brush to the moist 



TAWING, 689 

leather. When dry rub with a dry brush. For white leather 
use fine whiting in place of the buff color. 

A variety of oil leather which has been colored black on the 
flesh side, and the grain of which has not been scraped off, is pre- 
pared for shoemakers' purposes. It is manufactured from calf- 
skins scraped smooth upon the flesh side and blacked in the 
manner given later on. 

The so-called tioisted leather^ which is much used in some 
countries for straps, may also be called a variety of oil leather. 
It is said to excel in durability and suppleness. For manu- 
facturing it, depilate cowhides, which are generally used, by 
scalding with boiling water, and, after softening sufficiently, cut 
them into strips. Sew the strips into one long piece, and then 
sew the two ends of this together. After saturating with oil 
hang one end of the material on a hook and suspend a weight to 
the other. Then insert a stick between the two strips and after 
twisting them together, allow them to untwist in the opposite 
direction, repeating the operation several times and applying 
fat. By this operation the leather becomes heated and gradually 
saturated with fat. This method, as can be readily seen, will 
only serve as a partial substitute for fulling in oil. 

Peeller's Method of Tawing. 

Preller, on the 8th of March, 1852, obtained a patent in Eng- 
land for a peculiar method of preparing leather, but the merit 
of the invention is claimed by Theodor Klemm, of Pfullingen, 
who states that Preller bought the patent from him. Here- 
with we give a description of the process as patented by 
Klemm in Germany in 1849, which is substantially the same as 
the process patented by him in the United States in 1858. 
According to the specification, the process consists in impreg- 
nating the skins or hides with a mixture composed of certain 
animal, vegetable, and salty substances. The animal substances 
used are bullocks' brains, butter, milk, and animal fats ; of vege- 
table substances those are preferred which contain most starch 
and but little gluten, for instance, barley flour, rice flour, or starch 
by itself. The salts used are common salt and saltpetre. The fol- 
44 



690 THE MANUFACTURE OF LEATHER. 

lowing mixture gives good results: Barley flour 26 parts, bul- 
lock's brain 23, common salt or saltpetre 4, unsalted butter 6J, 
milk 12|, animal fat, such as neat's-foot oil or horse fat, 28. 
After mixing the butter and bullock's brain, add the flour grad- 
ually, then the fat, and finally the milk. The salt, the object of 
which is to preserve the butter and brain, can be added in the 
beginning. 

After depilating, soaking, and partly drying the skins or hides 
to be treated, place them in a cylinder and set the latter revolv- 
ing. The skins remain in the cylinder until by the motion 
imparted to them, the water still contained in them is uniformly 
distributed. The above mixture is then applied to the flesh 
side, and after replacing the skins in the cylinder, the latter is 
set in motion. The application of the mixture and revolving 
in the cvlinder are repeated until the desired success has been 
attained, thick skins requiring of course a longer time than thin 
ones. The skins while revolving in the cylinder may also be 
heated by the introduction of warm air. In place of a revolv- 
ing cylinder other means may be employed to impart to the 
skins the requisite motion. The succeeding operations to which 
the skins are submitted are the same as in the ordinary process, 
though the finishing is considerably facilitated by the foregoing 
treatment. 

The owner of the patent erected a factory in Southwark 
(London), in which the above process is used. The establish- 
ment has been considerably extended since the products are said 
to be much in demand. The mixture used is the one stated in 
the specification of the patent. The skins are spread out upon 
a table to receive the tawing mixture upon the flesh side. 
They are then placed in revolving stuffing-wheels, 8 to 9 feet in 
diameter and 5 feet deep. The skins are placed in the interior of 
the stuffing-wheels and removed through openings in the sides. 
The interior surfaces are provided with strong pegs, radiating 
from the centre, the object of which is to beat the skins vigor- 
ously to promote an equal distribution of the water contained 
in them, and a uniform absorption of the paste. The drums 
are driven by steam power, and can be made to revolve 



TAWING. 691 

quicker or slower according as the course of the operation re- 
quires it. 

To effect a drying, which is frequently required, the exhaust 
steam is conducted into a large receiver from which runs a pipe 
along the floor of the room. The pipe is connected with the 
interior of the stuffing-wheels by means of pipes and hollow 
shafts, the connections being opened or shut by means of cocks. 
The skins, after being revolved for a few hours (the time de- 
pending on their thickness), are taken out and examined, to 
ascertain whether the absorption and partial drying has been 
thorough and uniform. Skins not thoroughly saturated are, 
after hanging in an airy place for a short time, treated with a 
new application of the paste, and after replacing in the cylinder 
treated as before. The entire operation is repeated once more, 
after which cuts made in the skins should show by their uni- 
formity of color that the conversion into leather is complete. 
The skins, after a slight drying, are ready for finishing. 

Leather prepared according to Preller's process is called H B 
Groiun, and has proportionally less weight and thickness than 
tan leather. Experiments have shown that while 220 pounds 
of green hide tanned with bark give 110 pounds of leather, the 
same weight tanned by Preller''s process yields only SIJ pounds. 
The greater weight of tan leather is partly due to moisture, and 
as many tanners frequently produce intentionally thick and 
heav}^ leather by a peculiar mode of working, the smaller weight 
of crown leather would not be against it, and besides which, 
weight and thickness are not a criterion as to the quality of the 
leather. The greater strength of crown leather is due to the 
fibrous structure remaining unaltered. In tearing a piece of tan 
leather the structure is found to be more felty, while in crown 
leather the fibres lie in their natural position, closely pressed 
against each other. Experiments have shown that crown leather 
is far superior to tan leather as regards strength. A piece of 
crown leather ^ inch thick resisted a pull which tore tan leather 
f inch thick. A strip of crown, leather about J, inch wide, \ 
inch thick, and 2 feet 7 inches long, tore only with a load of 
682 pounds, while a strip of bullock's leather tanned with oak 
bark, and of the same dimensions, resisted only a load of 550' 



692 THE MANUFACTUKE OF LEATHER, 

pounds. A strap, consisting partly of crown leather and partly 
of tan leather, will always tear first in the part composed of the 
latter. 

Crown leather, on account of its strength with less thickness, 
is especially adapted for the manufacture of machine belts. 
Such belts being thin and pliable can be placed upon pulleys of 
small diameter, and are very durable. By using thick leather 
for belts the fibres on the outside must alternately expand, caus- 
ing an alteration in the original condition of tension, and con- 
sequently formation of cracks. Belts of a single thickness of 
crown leather are manufactured by simply joining the bevelled 
ends of the separate strips by means of a plastic mass. Belts 
for the transmission of greater power are made by placing two, 
three, or sometimes four thicknesses of crown leather upon each 
other, and sewing them together. In using these belts the 
motion is very gentle, 

Preller's method requires considerably less time than the 
ordinary tanning process. Calf-skins can be prepared by two 
operations in the wheel, each requiring about eight hours with 
a short interval between the two workings. The conversion 
into leather of the thickest bullock hide can be accomplished 
by Preller's process in two and a half days, while under the 
most favorable circumstances five to six weeks will be neces- 
sary by the ordinary method. 

As regards the capacity of- crown leather to resist water all 
experiences thus far seem to be favorable. Belts of it used in 
the open air and damp buildings have stood the test very well. 

By boiling ordinary leather in water, it becomes gradually- 
hard and inflexible, and by continuing the operation for half an 
hour it becomes brittle, or it frequently dissolves and becomes 
gelatinous. Crown leather subjected to the same experiment 
approaches gradually to the nature of horn, but only after 
several hours. 

The softness of crown leather makes it very suitable for the 
soles of house shoes, this quality and its strength with little 
thickness .recopimending it also for many other purposes. The 
back part of horse hides, which in the ordinary method is gene- 
rally cut qft' o.n a,Qcount of its thickness and not used, can by this 



TAWING. 693 

process be brought to such a state of softness, that it can be used 
together with the rest of the hide. Preller manufactures in this 
manner beautiful horse leather for carriage tops and boots, which 
is exceedingly soft and of great lustre. 

The theory of the process is easily understood by assuming 
that the fatty substances used, such as neat's-foot oil, horse- 
fat, and butter, on the one hand, and bullock's brain and milk 
on the other, play the same part as in the preparation of 
Erlanger leather and, that in a certain sense, as is the case in 
preparing oil leather, the other substances, such as flour con- 
taining gluten and starch, and common salt or saltpetre, have 
no other material function than the same substances in the taw- 
ing liquor for alumed leather. But excellent as no doubt the 
leather obtained by Preller's process is, it cannot be denied that 
its preparation does not excel in cheapness, and this is the point 
which every practical man has to consider. 

Butter, milk, and flour are commonly too expensive for 
the manufacturer to expect to be able to cover their cost by 
the price obtained for the leather produced, and this is very 
likely the reason why Preller's process has not been more gene- 
rally introduced. 

Preparatio:^^ of Klemm's Oil-Leather. 

This process is, so to say, an intermediate method between 
alumed and oil leather, alum being used in common with the 
first, and that of fats with the latter. According to the descrip- 
tion given in the patent,^ the process is as follows: — 

a. Manner of preparing the hides. — The hides are depilated by 
liming. A second liming as for alumed or tan leather is not 
required. To remove the lime, the hides are thoroughly 
washed and scraped and then placed in the bran steep until all 
the lime is removed, the raising of the hides being effected at 
the same time. They are then rinsed in fresh water and scraped 
clean upon the flesh side. 

h. Tanning is effected in the following manner : Prepare 

' Wiirtemberg'sches Gewerbeblatt, 1855, 9. 



694: THE MANUFACTURE OF LEATHER. 

warm alum liquor of the proportions previously mentioned, 
pour it over the hides, and, after thorough treading, allow them 
to remain in it for twenty-four hours. Then wash and com- 
pletely remove the excess of alum and salt by treading. Make 
a paste, composed for one hide of 8.8 pounds of brains, 15.4 
pounds of barley flour dust and about 8| ozs. of cod oil or 
melted horse grease, and dilute sufficiently with lukewarm water 
to allow of the hides being drawn through it. After immersion 
tread the hide until it has completely absorbed the fats and the 
gluten of the flour. After allowing the hide to remain in the 
vat overnight, hang it up the next day until it is half dry and 
then take it on the horse and remove the bran of the flour. 
After drying completely, and taking it once more on the horse, 
the leather is ready for coloring. It is suitable for all colors. 

By the removal of the alum and subsequent treatment with 
the tanning paste, this leather on exposure to water does not 
become fleshy like alurned leather. Beside it combines Avith 
all the desirable properties of oil and tanned leather the advan- 
tage of being stronger than the best tanned leather in consequence 
of the texture of the hide not being injured by liming, and that 
of resisting water better than ordinary tanned harness leather, 
and being more durable, as it contains no tannic acid. 

The further advantages of this process consist in that tan- 
ning is effected more quickly and fewer utensils and smaller 
outlay for tanning materials a-re required. 

Skins of deer, goats, sheep, and chamois tanned by this pro- 
cess combine all the advantages of glace leather with less con- 
sumption of tanning paste. 

Prof. Eeusch, who made experiments in regard to the strength 
of this leather as compared with the best harness leather, found 
the bearing strength of harness leather =7.100 pounds, of 
Klemm's oil leather= 13.112 pounds. 

The leather is colored in the same manner as glac^ leather. 
After coloring, the hides are once more greased with tallow or fish 
oil, and then finished with a hot plate. 

It will be seen that this process, which corresponds in many 
points with Preller's, does not differ materially from the more 
rational methods previously mentioned in speaking of the 



TAWING. 695 

manufacture of glace leather, and it is only natural that it 
should excel in strength. Prof. Fehling, who has made many 
conscientious experiments in regard to the matter, finds Klemm's 
statements entirely correct, and draws especial attention to 
the fact that Klemm's leather when dried after boiling for 12 
hours, showed the perfect cut of the leather, having only be- 
come somewhat more brittle. 

We have in the chapter on Mineral Tanning drawn the atten- 
tion of our readers to a method of preparing leather proposed by 
Dr. F. Knapp, who is well known through his valuable researches 
in regard to tanning processes. Knapp proposes to effect the 
tanning by the alternate use of salt solutions and soap baths. 
For preparing the salt solutions, alumina salts, aluminium sul- 
phate, or alum are employed, or ferric oxide, or chromium salts, 
the leather obtained by using the last two being of course more 
or less colored. For practical purposes alumina salts could only 
be recommended, as they, besides leaving the leather white, have 
the advantage of being found in commerce of an always uniform 
quality and great cheapness. Commercial potash-alum is with- 
out doubt the best material for the purpose. As regards the 
coDcentration of the solution, Knapp recommends 1 part of 
alum to about 20 parts of water. The soap bath is best pre- 
pared by dissolving 1 part of white soft soap in 20 or 30 parts 
of water. The soft soap, if not otherwise obtainable, can be 
prepared by boiling good clean fat or tallow with potash lye. 
The soap bath may also be prepared with ordinary white soda 
soap, but before using it, it must be heated to 96° to 98° F. 

The hides to be tawed b}'" this process, after depilating and 
preparing them in the usual manner, are placed in the salt 
solution, and after thorough handling are taken out from time 
to time and allowed to drain oft'. This is continued until they 
are thoroughly permeated with the salt solution, the process 
requiring, according to the thickness of the hides, and the 
.manner of preparation, 24 to 48 hours. After removal from 
the salt solution the hides are allowed to drain off, and then, 
while still moist, placed in the soap solution for 24 to 48 hours, 
being during this time frequently handled. After removal 
from the soap bath the hides, which are now thoroughly tawed, 



696 THE MANUFACTURE OF LEATHER. 

are rinsed in clean water and dried. Finishing and dressing are 
the same as for ordinary aluraed leather. The resulting pro- 
duct corresponds in all respects with that obtained by the 
ordinary process, but excels the latter in softness and supple- 
ness and greater permanence of the tawing. 

According to the same principle, a product resembling in 
many respects oil or chamois leather, is obtained by treating the 
thoroughly prepared skins in an acid bath, for the preparation 
of which hydrochloric acid diluted with 20 to 30 times its weight 
of water can be advantageously used. The best mode of pro- 
ceeding, according to Knapp's researches, is first to expose the 
hide to the action of the acid bath and then place it in the soap 
solution, repeating the operation twice or three times, or until 
a cut made in the hide proves it to be thoroughly tawed. 
After drying, the leather is freed from adhering soap with a 
sponge. 

A more simple and sure method, and one which is at the 
same time rational and in accordance with the theory of the 
tawing process, can scarcely be devised. The nature of the 
method is readily understood. 

As soap undergoes an alteration with solutions of alumi- 
nium salts, ferric and other salts, and a formation of a more or 
less voluminous precipitate of sebate or oleate of alumina, iron, 
etc., which is alm.ost insoluble in water, takes place, it will be 
readily understood that a complete tawing is effected by the 
formation of such combination, which by being formed in the 
skin tissue itself, must envelop the separate fibres of the tissue. 

The result obtained by the use of liquors and tawing paste, 
not very rationally composed, and transmitted to the tawer 
from remote ages, is by this process reached in a not only more 
simple but also surer way. 

And if we inquire about the expense the answer must cer- 
tainly be in favor of this process, for nobody can pretend that 
the tawing paste is cheaper than the soap solution. By trying 
this process once and seeing the results obtained from it, it will 
scarcely be possible to understand why this simple and easily 
managed method has not been more generally introduced, 



TAWING. 697 

though known since 1858. Progress in tanning appears to be 
much slower than in other branches of industry. 

A beautiful, white glazed leather of great softness and sup- 
pleness, can, according to Knapp, be prepared by macerating 
thoroughly cleansed skins of lambs or goats in a lukewarm 
saturated solution of stearine in spirit of wine and drying after 
thorough permeation. Though we are assured by experiments 
that this process furnishes an excellent product, especially as 
regards delicacy of color and suppleness, and a less pure and 
consequently cheap variety of stearine can be used, it seems to 
us that the use of spirit of wine as a solvent is too expensive 
for the purpose, especially as a part of it could only be regained 
by special utensils and apparatuses. If this defect could be 
remedied, the process might be used with profit and success. 

Note. — For matter in this chapter, the author desires to acknowledge his 
indebtedness to Gintl's Weissgerberei. 



PAET IX. 



CHAPTBE XLIII. 

DYEING LEATHEB. 

Section I. General Eemarks. 

Light is the source of all color, and it is the result of the 
vibrating motions of a very subtle substance, whicli the natural 
philosophers term "ether." 

The ether receives vibrations from self-lighting bodies, such 
as the sun, and spreads them in the same manner as the air 
spreads sound, with this difference, that the oscillating motions 
called "light" are brought forth many million times quicker 
than those of sound, because the ether is many million times 
finer than the air ; consequently, its vibrations are more rapid 
and intensive. 

The light entering our eye excites the optic nerve, producing 
a sensation called " vision," and thus light renders objects 
visible. 

Light itself is not a simple body, but is composed of various 
colors, of which we distinguish seven by separate names. 

All the colors observed in the organic and inorganic world 
around us are derived by reflection from the different colors, of 
which the white light, or sunlight, is composed. 

When we admit a ray of sunlight into a dark room, and there 
split it by means of a triangular glass, called a " prism," we can 
see, upon the screen opposite to the hole, as shown in Fig. 299, 
a series of bright colors, consisting of violet at the top, indigo, 
blue, green, yellow, orange, and red. This phenomenon is a 
"spectrum." 



DYEING LEATHEE. 



699 



Apparently there are seven colors; but there are only three 
primitive colors, namely, red, yellow, and blue, from which all 
others are derived. In fact, if we look very attentively at a 
spectrum, we soon realize the fact that violet, indigo, green, and 



Fig. 299. 




orange are the products of amalgamation of either two of the 
three primary colors, viz., violet and indigo from red and blue, 
green from blue and yellow, orange from 3^ellow and red. This 
is, in fact, the only natural explanation of this wonderful phe- 
nomenon. 

When speaking of primary colors hereafter, it must be borne 
in mind that we refer to the colors of the spectrum. There ex- 
ists no primary color substance, that is to say, a color represent- 
ing nothing but itself, in the true sense of the word. In fact, 
if we compare all known dye stuffs, we find that they always 
contain, besides the principal ones, more or less of some other 
color. This is not, of course, by bodily mixture, but their inti- 
mate atomic construction is such as to reflect more or less of 
the others, too, which are the components of the white light. 

For a man who studies the manifestations of nature, all the 
beautiful colors in which nature dresses plants, flowers, and 
trees, are simply wonderful objects of admiration. Uncertain 
colors there are none in the organic world ; wherever we turn 
our eye, we discover harmony and purity in the composition of 
colors and shades. To imitate this wonderful artist, nature, in 
coloring, should be the ambition of every dyer. 



700 THE MANUFACTUEE OF LEATHER. 

Of all the arts, none require such thorough knowledge, 
theoretical as well as practical, as the art of dyeing. Ohaptal, 
the great French chemist, therefore considers the dyer's art as 
the most useful and admirable of all. Indeed, if there is a call- 
ing which could make justly proud the man who practises it as 
an art, it is certainly that of the dyer. 

Chemistry is the abstract science, the part of which in devel- 
oping the art of dyeing consists in ascertaining, framing, and pre- 
senting the invariable rules, upon which all the dyer's operations 
must be based. The dyer is the practical, artistic executant of 
these rules ; all his operations are strictly chemical. The sim- 
plest mixture, the composition of the commonest mordant, in- 
volves chemical processes, the knowledge of which is indispen- 
sable to insure success. Of all his operations, a dyer should 
know the result in advance with mathematical accuracy; of 
his doings nothing should be left to blind haphazard. 

The scientifically educated dyer observes ; studies facts, 
always endeavoring to bring the chemical and physical phe- 
nomena occurring to him back to scientific principles, in order 
to ascertain their cause ; such studies constituting his ex- 
periences, which in all cases serve as guides. Such knowledge 
allows him to very quietly confront any problem which he may 
in the course of his operations encounter, giving at the same 
time an astonishing accuracy to his calculations for the elemen- 
tary composition, as well as for the production of colors and 
shades, which he desires to imitate. 

In composing our shades, there are, in fact, only the three 
primary Colors at our disposal, that is, red, yellow, and blue. 
The modifications, which these three colors are capable of under- 
going, and the limitless combinations into which they can enter 
with each other, enable us to reproduce any required color or 
shade. The part which water plays in all these modifications 
and combinations makes this element one of the most useful 
agents in the hands of a dyer. Indeed, water is for the dyer 
what the white color is for the painter; the more it is used in 
composing a dye-bath, the lighter becomes the dye; for the 
dyer, water means '' white," that is, absence of coloring. 

We shall try to illustrate this assertion by an example, for 



DYEING LEATHER. 701 

instance, a quart of concentrated solution of scarlet. "Concen- 
trated" means that we have dissolved in boiling water so much 
of the djestuff as the water was capable of dissolving, and de- 
canted the clear liquor from the sediment, if there was any, 
after cooling down to 50° F. If leather is dyed with a quart of 
this solution, there is produced a deep, nourished scarlet ; but 
for the next dye we will take only -^-^ of a quart of this solution 
and add yig- of a quart of water, so as to have again 1 quart of dye- 
liquor. The color thus produced is also well nourished, but has 
-jIq less depth than the former one. The addition of water and 
the reduction in the quantity of coloring solution have already 
produced a modification which is not likely to escape a dyer's 
eye. If we continue reducing the quantity of concentrated solu- 
tion at the rate of 10 per cent., and increasing the quantity of 
water at the same rate (that is, making the quantity of dye- 
liquor=l quart), we will arrive at a point where our dye-liquor 
consists of only jL- quart of the original concentrated solution of 
scarlet red, and -^-^ quart water. The color of the material dyed 
in such a bath is, of course, proportionately lighter. Each time 
that we have reduced the quantity of concentrated solution of 
dyestnff by j^q, and added yig- more water instead, we have 
altered the original color, and have produced nine modifications 
of the first, or ten grades of scarlet-red altogether. 

The result of such an experiment is what is called a "gradu- 
ated line of a color," and each degree of it is called a " modified 
color" of such a line. 

A close examination and dissection of a spectrum discloses 
the fact that there are not only seven, but actually twelve, colors 
contained in it, viz : Red at the bottom, and following in suc- 
cessive order upward, red-orange, orange, yellow-orange, yellow, 
yellow-green, green, blue-green, blue, blue- violet, violet, and 
red-violet. 

If we take three very bright artificial dyestuffs (red, yellow, 
blue), products of coal-tar, better known as aniline colors, whose 
chemical composition allows of their perfect union by mixing 
their solutions with one another, we can produce these twelve 
colors of the spectrum by mixture, out of three we can form 
twelve, nine of them being binary colors, so called from being 



702 THE MANUFACTURE OF LEATHER. 

composed of two of the three primary colors. There is no 
difficulty in producing such a representation of a spectrum upon 
leather. 

The measure is for a leather dyer what scales and weights 
are for the chemist — they are proof and evidence. A quart re- 
presents a unit, which can be divided, and of which we can take 
only one hundredth part or any fraction we desire or require — 
where figures corroborate, error is not probable. One quart of 
concentrated solution of scarlet-red is mixed with one quart of 
concentrated solution of a yellow dyestuff. If these dyestuffs 
represent the true elementary colors, and this bath is applied to 
dyeing leather, properly prepared, the product must be a true 
orange, this color being composed of red and yellow in equal pro- 
portions. But if only 0.25 of a quart of yellow dyestuff solution 
is mixed with 0.75 of red, the compound will be red-orange. If, 
on the other hand, these proportions are reversed, that is, 0.25 
of a quart of red dye-liquor mixed with 0.75 of yellow, the pro- 
duct will be yellow-orange. As red and yellow in equal pro- 
portions form the true orange, it follows that red-orange lies on 
one side of this binary standard color (toward red), and yellow 
on the other (toward yellow). We call a " binary standard" 
that compound color which is obtained by mixing together the 
liquors of two primary colors in equal proportions. 

By operating in the same manner with the solutions of a 
yellow and a blue dyestuff, yellow-green, green, and blue-green 
are produced. 

The solution of a true blue dyestuff, such as is spoken of in 
enumerating the prismatic colors, being brought together with 
that of a pure red, in the above proportions, the blue-violet, 
violet, and red-violet of the spectrum are produced. 

It should be borne in mind, however, that in all cases the 
dyestuffs which are used for such operations must be of such a 
nature as to allow of their combination, that is, of their perfect 
embodying one into the other, if mixed in solution ; so that, 
after dj^eing, no separate colors can be distinguished upon the 
material. 

If in the transition from one prismatic color to another we 
were at each step to exchange only one hundredth part of the 



DYEIXG LEATHER. 703 

one for an equal quantity of the other, it is evident that in- 
finitely more colors might be produced; but these slight modifi- 
cations would be hardly distinguishable. To our eye the whole 
scale would appear as an amalgam, like the spectrum of the 
white light. But if it is considered that either of the two 
colors can be graduated, that is, progressively changed from 
very dark, nearly black, to light and very light, nearly white, 
it may readily be imagined that thousands of colors can be pro- 
duced by this very simple means. We say purposely colors, 
because we mean not shades,^ of which we shall speak later. 

The slightest alteration of "white is at once perceptible; while 
a considerable proportion of any other color can be added to 
black, before the modification becomes apparent to even the 
trained eye. 

Transition of colors through their countless modifications can 
be very properly illustrated by a so-called color-ball, having for 
its equator, as it were, a zone consisting of the primary and 
binary colors, white for its north pole and black for its south 
pole. 

But to return to our circle of normal colors : All colors 
growing out of a primary color must be classed under that 
denomination, until they reach the compound of the primarv 
with the nearest binary standard color. For instance, all colors 
originating in red are to be classed as reds, until the red-orange 
is reached, with this difference, however, that they are distin- 
guished at first, second, third, etc., reds, according to the degree 
of modification the red has undergone. Thus, if red is denomi- 
nated as No. 15 on the side toward blue, it would signify that 
this red contains 15 per cent, of blue ; as only with the addition 
of 25 per cent, blue the red becomes red-violet. The same 
nomenclature ought to be used for blues and yellows. 

From the above it is easy to see that a precise knowledge of 
this circle is suf&cient to determine a color at once, thus enablins; 
the dyer to reproduce it. The series of modifications of which 
any primary or binary color is susceptible is collectively called 
the "category" of that color, and we wish it here to be under- 
stood that the category is not identical with "shades," though 



704 THE MANUFACTURE OF LEATHEE, 

the erroneous application of this term is quite general and 
popular. We know what a simple (or primary) color is, of 
which there are only these three : red, yellow, and blue ; we 
know also, that either two of these simple colors combined with 
one another form a binary (or secondary) color. But a " shade" 
is the result of the combination of one binary color with one 
or two other binary colors not belonging to the category of the 
former. 

Brown, for instance, is a shade. All the browns are oranges 
shaded more or less with blue or violet. When a dyer is called 
upon to reproduce a certain brown, the first thing he has to do 
is to ascertain what kind of orange is the base of it, whether 
red, pure, or yellow orange. By contrasting various browns 
with another, it is easy to determine Avhether the particular 
brown in question belongs to the reddish or yellowish category; 
the category once defined, there is no further difficulty in decid- 
ing upon the base of the dye-bath, whether reddish or yellowish- 
orange. This base is then to be composed, then to be shaded, 
and the bath is ready for dyeing; if the diagnose of the orange 
is correct, and the shading carefully done, the dyer cannot fail 
in producing the exact brown. 

From this it may be seen how indispensable for a dyer it is to 
thoroughly understand his binary colors; upon this knowledge 
depends, in fact, the whole art of producing the various shades. 
The whole variety of binary colors are so many bases for all 
imaginable shades. 

The shades, in their turn, are again susceptible of infinite 
modification, that is, of being rendered light by the addition of 
water, or darkened by the chemical action of various salts, such 
as sulphate of copper, bichromate of potassium, etc., added to 
the dye-bath. The whole range of such modifications, from the 
lightest to the darkest hue, is called the "categorj^ of a shade." 

In reproducing a given shade, the practical dyer will rather 
from the beginning sadden a little less than too much, because 
he has it always in his power, and it is easier to increase the 
saddening, than to diminish it, after it has been once produced. 

The manufacture of dye-stufi's from coal-tar, the so-called 
aniline colors, has attained a high state of perfection, although 



DYEING LEATHEE. 705 

this fraitful field of manufacturing chemistry is, as yet, only 
partly explored and still less practically cultivated ; and we are 
daily greeted by the news of improvements, inventions, and new 
and astonishing discoveries in this line. There are now already a 
number of such artificial dye-stuffs in the market, which directly 
produce a variety of desirable shades, relieving the dyer of the 
trouble and the cost of experiments to compose them. Still, it 
is very often necessary to mix these colors for the production of 
certain shades. In such cases it ought to be borne in mind that 
the base of every shade is a binary color, which must be ascer- 
tained and defined before beginning the mixing operation, in 
order to save trouble, time, waste, and positive loss. Dyeing 
with aniline colors will be enlarged upon in Section V. of this 
chapter. 

Section II, Mordants. 

Mordants in the widest sense are bodies having the power of 
fixing certain coloring matters upon materials to be dyed. But 
in the narrower sense mordants are also certain bodies which 
possess the power of changing the natural color characteristic to 
coloring matters, thus leading to the production of several shades 
with one and the same substance. In as far as many bodies 
available as mordants can produce, on meeting with other sub- 
stances partly organic and partly inorganic, characteristic colors, 
they may be designated as color-yielding substances. 

The mordants generally used can be divided into three groups, 
viz., acids, bases, and salts. 

Acids. 

Acids are generally compound bodies sour to the taste, and 
capable of changing blue vegetable colors to red. By combin- 
ing with bases they furnish combinations which have neither 
the external characteristics of the acid nor those of the base 
combined with it, in fact are new bodies. Such combinations of 
acids with bases are called salts. In the process of combination 
the acids are neutralized by the bases, the same being true in a 
45 



706 THE MAiSrUFACTURE OF LEATHER, 

reverse sense as regards the bases. Acids are divided into 
mineral and organic acids. 

Sulphuric, nitric, and hydrochloric acids are the principal 
mineral acids employed in dyeing leather, and they will be 
described separately. 

Sulphuric Acidj 

or oil of vitriol, is a combination of sulphur with oxygen. In 
a concentrated state it is a caustic substance, which energetically 
attacks organic bodies and destroys them under a black or brown 
coloring, and is best kept in glazed earthenware or glass ves- 
sels hermetically closed. Sulphuric acid is mixable with water 
in all proportions, and by sufficiently diluting loses its strong 
caustic property and yields a fluid more or less clear. Diluting 
the acid with water requires to be done carefully, as the great 
attraction which this acid has for water causes a strong develop- 
ment of heat, in consequence of which phenomena resembling 
explosions of steam take place, and with careless handling the 
workman might be injured by the caustic fluid. Many have 
suffered permanent injury to health or have lost eyesight by 
carelessly diluting sulphuric acid. With the exception of dis- 
solving indigo, which requires concentrated sulphuric acid, only 
dilute sulphuric acid is used in dyeing leather. The best method 
of diluting is to place the water in a clay or porcelain vessel, 
or very diluted acid in a wooden vat, and to pour the concen- 
trated acid into it in a thin stream, a glass rod being used to 
mix the acid with the water as it flows in. Under no circum- 
stances should water be poured into concentrated acid. 

Nordhauseu, or fuming sulphuric acid, differs from common 
sulphuric acid in its mode of preparation and that it contains 
less water, and is in a certain sense more concentrated than 
ordinary sulphuric acid, which is due to its percentage of anhy- 
drous acid. For all other purposes except for dissolving indigo, 
the use of ISTordhausen sulphuric acid would be sheer waste, as 
the cheaper American acid, when diluted with water, furnishes 
the same product as fuming acid, and besides has the advantage 
of being less contaminated. 



DYEI^^G LEATHEE. 707 



Nitric Acid 



Is a product of the action of sulphuric acid upon nitrates, and 
is generally prepared by distilling nitrate of potash or of soda 
with sulphuric acid. The strongest nitric acid emits thick gray 
fumes when exposed to damp air, because its vapor, though 
itself transparent, readily absorbs water from the air, and con- 
denses in minute drops of diluted nitric acid which compose 
the fumes. Nitric acid exerts an energetically oxidizing influ- 
ence upon all organic substances, and is best kept in vessels of 
glass or earthenware. It is mixable with water in all propor- 
tions, and in a diluted state furnishes a colorless fluid of a 
strongly acid taste. 

Nitric acid suffers decomposition when exposed to the light, 
and it frequently happens that bottles filled with concentrated 
nitric acid burst on exposure to light, in consequence of the 
pressure of the accumulation of gases in the upper part of the 
bottle. Such acid, decomposed by the action of light, assumes 
a red-brown, and under certain circumstances, green color, and 
acquires the property of emitting, when exposed to the air, 
brownish- red vapors of hyponitric acid, etc., which violently 
irritate the respiratory organs. Such acid, known as red or 
fuming nitric acid, is very serviceable for certain purposes, and 
is especially manufactured and brought into commerce. 

Ordinary, as well as fuming, nitric acid is exclusively used 
by the dyer for sharpening certain baths, and in the preparation 
of some mordants ; for all other purposes it can be replaced by 
other and cheaper acids. The characteristic property of nitric 
acid of coloring nitrogenous, organic substances, yellow, which 
is utilized in silk and wool dyeing, cannot be made use of in 
coloring leather, as the acid would act too strongly upon the 
leather substance. 

Hydrochloric Acid 

Is a solution of the gaseous combination of chlorine and hydro- 
gen in water, and is a yellowish fluid which emits white fumes 
when exposed to the air, and has a suffocating odor. It is 



708 THE MANUFACTURE OF LEATHER. 

rnixable with water in all proportions, and when sufficiently 
diluted yields a colorless fluid of a perceptibly acid taste. 

On account of its cheapness, hydrochloric acid can be advan- 
tageously used where only the action of an acid is required, as, 
for instance, in neutralizations, etc. 

Of organic acids, the following are of interest to the dyer: — 

Acetic Acid 

Is found in nature as a constituent of salts, occurring in some 
juices of plants, and also forms a constituent of certain combi- 
nations of the animal body. It is a combination of carbon, 
hydrogen, and oxygen. Yery concentrated acetic acid is slightly 
caustic, but diluted with water it is entirely innoxious. 

Pyroligneous acid — obtained by the dry distillation of wood, 
■and as a by-product in burning charcoal — is dilute acetic acid. 
It is much used, especially for dyeing leather, in consequence of 
its containing certain empyreumatic substances. It possesses the 
property of imparting to the black color, produced with the 
assistance of the so-called black vat, a pure tone of color, this 
being the reason why it is almost exclusively used for iron 
liquor for black, 

vlcetic acid, whether produced by the oxidation of alcohol, 
or dry distillation of wood, is mainly used for the preparation 
of the various acetates employed in dyeing, and as it attacks 
the leather substance less energetically than mineral acids, is 
preferably used for acidulating dye-batbs. 

Oxalic Acid, 

Known also by the name of acid of sugar, is, like acetic acid, a 
combination of carbon with hydrogen and oxygen. It is a 
constituent of many plant juices, being found in the leaves of 
the wood-sorrel, in the stalks of rhubarb, in some seaweeds, and 
in certain lichens. Oxalic acid, like acetic acid, is used for 
preparing dye-baths. It is very poisonous, the antidote being 
chalk of magnesia. 



DYEING LEATHER. 709 

Citric Acid and Tartaric Acid. 

Citric acid is a constituent of plants, and occurs in the juice 
of lemons, currants, gooseberries, and other kinds of fruit. Tar- 
taric acid is prepared on a large scale from crude tartar, which 
is deposited in wine casks. Both acids are occasionally used as 
additions to dye-baths, though they probably possess no special 
virtues entitling them to preference before the other acids. In 
commerce both acids are found in the form of colorless crystals, 
or crystalline masses, readily soluble in water, and yielding 
solutions of a pure acid taste. 

Bases. 

Bases comprise all compound bodies capable of combining to 
salts with acids. Bases soluble in water have in common the 
property of re-coloring vegetable substances blue after its color 
has been changed to red by acids. Considering bases in the 
above sense that they can combine with acids to salts which 
show neutral reaction under certain circumstances, we may 
speak of a neutralization of acids by bases and employ thein for 
that purpose. The majority of bases, which are either metallic 
oxides (mineral bases) or combinations containing nitrogen, 
hydrogen, and carbon, and sometimes oxygen (organic bases), 
are insoluble in water but soluble in acids, while, on the other 
hand, bases with insoluble acids and soluble in water will gene • 
rally yield solutions containing the newly formed salt. On 
account of the dissolving effect which bases exert upon many 
insoluble substances by reason of the nature of the acids, they 
are as such of but little importance to the dyer. These are the 
following: — 

Potassium Hydrate and Sodiura Hydrate. 

The first body is almost exclusively obtained by the action of 
caustic lime upon solutions of potash. It dissolves very readily 
in water, has a strongly alkaline reaction, and exerts a powerful 
caustic effect by reason of its capability of dissolving many organic 



710 THE MANUFACTUEE OF LEATHER. 

substances (among others animal skin). Caustic potash can 
generally be replaced by the cheaper potash, soda, or ammonia. 
The action of sodium hydrate, or, as it is commonly called, 
caustic soda, is very similar to that of caustic potash, and is 
frequently used as a substitute for the latter substance, which 
it resembles in appearance. 

Ammonia, 

In a pure state ammonia is a colorless gas of a pungent odor. 
It is a combination of nitrogen and hydrogen, and is produced 
by heating a mixture of caustic potash or caustic soda, or, what 
is cheaper, caustic lime, with sal ammoniac. 

Although ammonia is a cheap article of commerce and is in 
general use in dyeing, urine of human beings and of carnivorous 
animals is almost exclusively used in the so-called English 
method of steam dyeing. Besides there are other dyers opposed 
to progress who still make use of antiquated receipts and retain 
the disgusting use of urine, although the employment of ammonia 
is not only cheaper but also better. We consider it unnecessary 
to enter into a discussion of this antiquated substitute for 
ammonia, and will only remark that putrefied urine can only 
be used as it only acquires the properties of a substitute for 
ammonia in that state. Urea, a characteristic constituent of the 
urine of carnivorous animals, undergoes decomposition in the 
putrefaction of urine, in consequence of which ammonium car- 
bonate, i. e., the active principle of putrefied urine, is formed. . 

Lime. 

Caustic lime, or burnt lime, is the oxide of calcium. The 
purest product is obtained by burning white varieties of marble, 
while ordinary limestone yields lime contaminated with alumina, 
silicious earth, iron, etc., the quality of the lime depending on 
the quantity of these impurities. The fewer impurities lime 
contains, the better it is for dyeing purposes. Lime-water, or 
milk of lime, is much used, not only for neutralizing purposes, 
but also for separating acids from solutions; the preparation 
of caustic lyes being, for instance, a process in which the power 
of lime of precipitating carbolic acid in the form of insoluble 




DYEING LEATHER. 711 

carbonate of lime is utilized for separating the carbonic acid 
from the oxides of potassium or sodium. 

Other bases by themselves are not used in dyeing, only the 
combinations of a few with acids, i. e., their salts, being employed. 

Organic bases, which are generally derivatives of ammonia, 
and closely allied with it, are also not used by themselves as 
mordants, though in certain combinations they furnish highly 
valued coloring matters. 

Salts. 

Salts are combinations of acids with bases, no matter whether 
the acid or the base is of organic or vegetable origin. The salts 
can be divided into acid, neutral, and basic salts, according to 
whether their acid is incompletely or completely neutralized, 
and the base is also completely neutralized, or whether a non- 
saturated part of the latter is present in excess. Acid salts are 
such as contain an excess of acid, basic salts, such as contain an 
excess of base, while the terra neutral salts is applied to those 
which contain exactly the quantity of base necessary for the 
neutralization of the acid. Soluble acid salts have generally an 
acid reaction, and basic salts mostly an alkaline one, while the 
majority of the actually neutral salts have also a neutral reac- 
tion. Exceptions to this rule seldom occur. 

While the actual salts consist, as stated, of acid and base, and 
are, therefore, oxygenous combinations, there is another class 
of salts which contain no oxygen, and must be considered as 
pure combinations of metals with another element or with a 
combination. They are called haloid salts, chlorine, bromine, 
iodine, etc., being instances of this class. One of the most com- 
mon examples of these salts is common salt, which is composed 
of the metal sodium and the element chlorine, and is, therefore, 
chemically known by the term sodium chloride. 

In the following we give a compilation of salts of greatest 
importance to the dyer. 

Sulphates. 

Ferrous sulphate^ or green vitriol^ is a combination of ferrous 
oxide with sulphuric acid. It is used for making mordants, 



712 THE MANUFACTURE OF LEATHER. 

especially for black, gray, and violet, and for preparing the 
indigo vat. For the latter purpose, it should be as pure as pos- 
sible, while for preparing iron liquor, ferrous sulphate, even if 
turned strongly brown, can be employed. It is also used in the 
production of Berlin blue. 

Capric sulphate^ or hlue vitriol^ contains cupric oxide and sul- 
phuric acid, besides water. It is brought into commerce in 
transparent or semi-transparent prisms of a dark-blue color, 
wdiich have an acid metallic taste. They are soluble in -i parts 
of cold water and 2 parts of boiling water. 

Under the name of Salzburg vitriol, double eagle vitriol, 
etc., a variety of cupric sulphate is brought into commerce, 
which, besides being mixed in various proportions, contains sul- 
phate of zinc. Both varieties are used in dyeing glove leather. 

Cupric sulphate is very poisonous ; a small quantity taken 
inwardly produces severe vomiting. 

White vitriol, or zinc sulphate, is a combination of oxide of 
zinc with sulphuric acid, and is obtained by crystallization from 
a solution of zinc in dilute sulphuric acid. The crystals are 
clear as water, and have a nauseously metallic taste. They are 
readily soluble in water. White vitriol, which is very poisonous, 
is almost exclusively used in the so-called English method of 
steam dyeing. 

Aluminium sulpihate consists of sulphuric acid and aluminium. 
It is found in commerce in the form of bricks or plates of a 
white or grayish-white color and an acid taste. By boiling 
aluminium sulphate with water, it is gradually and completely 
dissolved, and yields a colorless fluid, with an acid reaction. 
The solution can be advantageously used in all cases where 
alum was formerly employed, especially as it contains no excess 
of sulphuric acid, and constitutes the only component part of 
alum which makes the latter valuable for dyeing purposes. 

Alu7n, in the narrower sense of the word, is such a double 
combination of two sulphates, which will always contain alumi- 
nium as a sesquioxide, when solutions of aluminium sulphate 
are brought together with sulphates of suitable simple oxides. 
According to the nature of the sulphate combined with the 
aluminium sulphate, the following principal distinctions are 



DYEING LEATHEE. 713 

made in the varieties of alum: Potasli-alum, ammonia-alum, 
and soda-alum. Soda-alum is more readily soluble in cold water 
than the others. For dyeing purposes potash-alum is most 
generally used, or as a substitute for ammonia-alum, or a mix- 
ture of both in varying proportions. It is of little importance 
which variety is used, only in buying his supply the dyer should 
be careful not to be overcharged by paying the same price for 
ammonia-alum, which is always cheaper than potash-alum. For 
the purpose of recognizing whether potash-ahim is pure, rub a 
piece of it together with caustic lime and moisten the mixture 
with water. The presence of ammonia will be readily detected 
by its characteristic odor. It is also worthy of consideration 
that alum frequently contains iron, which renders it unsuitable 
for many purposes, as the percentage of iron frequently produces 
with the coloring matters other shades than those intended. In 
order to obtain a pure red with madder, alum containing iron 
must be especially avoided. It is, therefore, well to subject the 
alum to a test before using it. This is readily effected, accord- 
ing to Prof, Eange, by throwing a piece of the alum to be tested 
into a solution containing 15J grains of potassium cyanide in 7 
ounces of water. If the color of the surface of the alum remains 
unchanged, it is free from iron^ but contains iron in case blue 
spots make their appearance. This test is entirely reliable for 
alum in pieces ; it is claimed to be equally reliable for pulverized 
alum and alum solution. 

A variety of potash-alum which is especially highly esteemed 
is the so-called cube alum. It is distinguished from the ordi- 
nary alum by the form of its crystals, and has the further 
advantage of its solution being entirely free from iron. 

"Burnt alum" is almost exclusively used for fixing coloring 
matters which by themselves have not sufficient capacity to ad- 
here to the fibres. But it is not generally used in the above 
form, but rather by preparing first a solution in which by 
adding acetate of lead to alum solution, aluminium is present 
as aluminium acetate, and using the solution as a mordant (red 
liquor). 

Chromium alum is also sometimes used for dyeing purposes, 
especially in dyeing with aniline colors. It is found in com- 



714 THE MANUFACTURE OF LEATHER. 

merce in dark violet crystals, which yield with water a solution 
of the same color. On heating, the aqueous solution turns green, 
but gradually reassumes its original color. 

Nitrates. 

Ferric nitrate and lead nitrate are the only ones of the series 
which have any importance for the dyer. 

Ferric nitrate is formed by dissolving iron in nitric acid. The 
commercial article is a brown liquid of the consistency of syrup, 
has an acid reaction and a strong taste of ink. It is mixable 
with water in all proportions, the diluted liquid yielding a 
strongly colored fluid. This salt, which can also be prepared in 
a solid form, can be advantageously used for black and blue 
colors, in the latter case with the assistance of yellow prussiate 
of potash. • 

Lead nitrate is prepared by dissolving litharge in nitric acid. 

It forms white crystals of a nauseously metallic taste, which 
are difficult to dissolve in cold water, but readily so in boiling 
water. Lead nitrate, like all other soluble lead combinations, is 
poisonous. This salt, Avhich is not generally used in leather 
dyeing, lead acetate being mostly substituted for it, has only 
become of importance since the introduction of aniline colors. 

Chlorides. 

Sal ammoniac comes into commerce either in fibrous cakes 
(sublimated sal ammoniac) or in small crj^stals (purified sal 
ammoniac). It is readily soluble in water, and yields a colorless 
solution of a neutral reaction and a peculiar salty taste. In 
dj^eing it is used as an addition to the so-called tin composition. 

Ferric chloride is similar to ferric nitrate, and is used in a like 
manner. 

Stannous chloride (tin salt) is of but little importance to the 
leather dyer, as leather, especially alumed leather, is not im- 
proved by it. 

Stannic chloride forms the most active constituent of the solu- 
tion of tin in nitric and hydrochloric acids, or in nitric acid and 
sal-ammoniac, which is known by the name of tin composition 
or physic. Pure stannic chloride is soluble in water, and yields 



DYEING LEATHER. 715 

an almost colorless solution of a strongly acid reaction, which 
can be successfully used as a substitute for all the various tin 
compositions. 

Common salt (sodium chloride) is so well known that it 
requires no description. It plays a more important part in 
tawing than in dyeing. 

Acetates, 

Ferric acetate in a pure state forms a reddish-brown liquid of 
an ink-like taste. It is never used in this form for dyeing pur- 
poses, but it constitutes the active principle of the various 
essences used under the name of iron liquors, which are ob- 
tained by dissolving iron in vinegar, sour beer, sour wine, or 
wood vinegar. The following directions for the preparation of 
a black, vat can be recommended: Place a barrel upright and 
provide it with a perforated false bottom six inches above the 
true one. Upon the false bottom pile a layer of old iron or iron 
filings, and upon this a layer of iron, which should be rusted as 
much as possible. Upon the iron place a layer of young alder 
bark with the addition of a few nutshells and a few buckthorn 
berries. Upon this bring another layer of old iron, upon this a 
layer of alder bark, nut-shells, and berries, and continue the 
layers alternately until this barrel is full, and then fill the barrel 
with an acid liquid such as vinegar, sour beer, juice of unripe 
fruit, etc. The first liquid is generally heated before pouring it 
into the barrel. A part of the fluid is drawn off from time to 
time through a cock near the bottom of the barrel and poured 
back over the material, whereby a movement is originated in 
the barrel which exerts an advantageous effect. Some leather 
dyers use, besides the above-mentioned materials, some verdi- 
gris, which has by no means an injurious effect. 

The black vat cannot be successfully used before it is six 
months old, and can only be called good after it is one year old. 
The black vat is not only used for dyeing oil leather, but also 
for coloring alumed leather upon the flesh side. The iron solu- 
tioD prepared in the above manner is, as a rule, something over 
2°B. 

Aluminium acetate forms the actually active constituent' of the 



716 THE MAXUFACTUEE OF LEATHER. 

red liquor, which is generally prepared by mixing hot solution 
of alum, or better of aluminium sulphate, with plumbic acetate. 
'The resulting solution, which is as clear as water, can be imme- 
diately used after adding some sodium sulphate in order to com- 
pleteh^ separate the lead. According to Leussen, the following- 
are the best proportions: Dissolve 191^ pounds of aluminium 
sulphate and 15 J pounds of soda in 37 gallons of water, and add 
to this solution a solution of 228f pounds of plumbic acetate in 
18J gallons of water. After settling and removal of the white 
precipitate of plumbic sulphate by filtering, the mordant can 
be immediatel}'" used. Aluminium acetate is an indispensable 
mordant for the calico dyer, but is of less importance in dyeing 
alumed leather since the skins, on account of the percentage of 
aluminic salts worked into them by the tawing process, do not 
especially require a mordant. In dj^eing oil leather this mor- 
dant can be advantageously used. 

Plumbic acetate (sugar of lead) is prepared by dissolving 
litharge in vinegar and evaporating the resulting solution. It 
is chiefly used for preparing the red liquor and for the produc- 
tion of chrome yellow upon leather. For the latter purpose it 
is better to use the basic acetate of lead, it being less injurious 
to the leather. It is prepared by boiling solution of plumbic 
acetate with an excess of litharge and is found in commerce in 
solution under the name of vinegar of lead. Both salts are 
violently poisons, and when taken inwardly or even handled 
carelessly produce symptoms of colic. 

Cupric acetate. In commerce this salt is known as verdigris, 
crystallized verdigris, distilled verdigris, etc. It is but slightly 
soluble in alcohol and requires five times its weight of boiling 
water for a complete solution. It forms bluish-green crystals 
of a nauseously metallic taste, which represent the actually neu- 
tral salt, i. e., the crystallized or distilled verdigris. 

Under the general name of verdigris a basic acetate comes 
into commerce in two varieties differing widel}' in appearance. 
One forming a mass of a pale blue color sprinkled through with 
a quantity of cr3'stalline spangles, while the other is a greenish 
mass in which the cr3^stalline spangles are less perceptible and 



DYEING LEATHER. 717 

have a more earthy appearance. The difference in appearance 
is caused by the presence of different basic salts. 

Verdigris can be used as a substitute for crystallized verdi- 
gris in all cases, it being only necessary to use a larger quantity 
of it, or, what is preferable, to dissolve it with an addition of 
acetic acid which effects a ready and complete solution. In- 
dependent of being the material used for the manufacture of 
Schweinfurth green, verdigris is only used as a mordant in dye- 
ing with garancine or as a ground for the production of brown 
shades in dyeing with potassium ferrocyanide. 

Tartrates. 

Of this series of salts, the only of any importance to the dyer 
is the 'potassium, hitartrate. 

It forms a crust in the fermenting vessels, and after reaching 
a certain degree of thickness is broken out and brought into 
commerce as crude tartar. It forms grayish-brown masses, 
which, when derived from red wine, have a dirty red color. 

Cream of tartar is found in commerce either as colorless, 
transparent, and hard crystals, or as a powder. It dissolves in 
200 parts of water of 158° F., and in 20 parts of water of 185° 
F. It is insoluble in alcohol. 

Tartar is used in leather dyeing for the purpose of increasing 
the durability of the colors. Tartar used at the same time with 
ammoniacal liquids gives a good mordant. 

The ch(3mical action of tartar in the different dyeing pro- 
cesses is not yet thoroughly explained. Its power of keeping 
lime salts and many metallic oxides in solution, is of especial 
importance as a protective against the injurious effects of hard 
water which has frequently to be used, and exerts a disturbing 
influence upon the progress of the dyeing process on account of 
its richness in lime salts. 

Carlonates. 

Of this series of salts only tAvo are of importance to thc'dyer: 
Potassium carhonate (potash) is almost exclusively obtained 

by lixiviating wood ashes and evaporating the resulting lye. 

It forms a mass of a dark-gray, blue-gray, or bluish color, which 



718 THE MANUFACTURE OF LEATHER. 

readily becomes moist on exposure to air and deliquesces. It 
is easily soluble in water, yielding a solution of a lye taste and 
strongly alkaline reaction (crude potash). Purified potash, on 
the other hand, is always white and also soluble in water. 
Different varieties of potash are known in commerce and desig- 
nated by various names according to their quality and derivation, 
such as pearl ash, Russian potash, lllyrian potash, American 
potash, etc. 

As potash is always used in solution it is recommended that 
the dyer subject it to the inexpensive purifying process, which 
consists in pouring over it about the same quantity of water. 
The carbonate passes into solution, and by placing the vessel in 
the air and pouring off the solution, it can readily be separated 
from the larger portion of sulphates and chlorates which form 
tlie most common contaminations. The residue is washed out 
with water, which can be used for purifying a fresh quantity of 
potash. 

Potash is partly used for cleansing the skins before dyeing, 
and partly as an addition to aluminium sulphate whereby the 
sulphuric acid is saturated. It serves also to remove any excess 
of oil used in preparing many skins and frequently for the 
neutralization of acid liquids, whereby effervescence, caused by 
the escape of carbonic acid, takes place. Potash is also used as 
mordant in the English method of dyeing glove leather. 

Sodium carbonate (soda) is used by the dyer chiefly for neutral- 
izing purposes, for dissolving coloring matters, and as a consti- 
tuent of mordants. In most cases it can be employed as a 
substitute for potash. 

It remains to mention a few salts of other acids of importance 
to the dyer which could not be included in the above groups. 

Potassium hichrom,ate is composed of chromic acid and potas- 
sium. This salt, which is very poisonous, is chiefly used with 
dye-woods for the preparation of black colors, the development 
of which from the coloring matter of the dye-woods is due to 
the oxidizing action of the chromic acid. By mixing potassium 
bichromate with lead salts (nitrate or acetate of lead in solution). 

Lead chromate is obtained as a yellow, pulverulent precipitate, 
which is highly esteemed as a color (chrome-yellow). In dyeing 



DYEING LEATHER. 719 

leather it is most conveniently used by subjecting the leather 
previously mordanted with lead acetate to the action of a solu- 
tion of potassium chromate. 

By heating potassium chromate with concentrated sulphuric 
acid, a green solution is obtained from which separates the 
previously described chrome-alum in the form of crystals. 

Yellozv pj'ussiate o/'potesA (potassium ferrocyanide) is brought 
into commerce in the form of yellow crystalline masses more or 
less saturated, which yield a white powder. The salt is readily 
soluble in water, especially if previously heated, and is distin- 
guished by its bitter salty taste and neutral reaction. It is not 
poisonous. Yellow prussiate of potash is not used as much as a 
mordant for fixing other colors, as for a coloring matter by itself, 
since it possesses the power of yielding at once a beautiful blue 
color, known as Berlin blue, on coming in contact with iron 
salts. 

This blue, which can also be prepared by the action of yellow 
prussiate of potash upon sulphate of iron and simultaneous 
exposure to the air, is convenient for dyeing leather, since 
nothing further is required than brushing the skins previously 
mordanted with yellow prussiate of potash with a weak solution 
of nitrate or acetate of iron, or, vice versa, treating skins mor- 
danted with iron solution with yellow prussiate of potash. 
Another somewhat different method of dyeing with Berlin blue 
is to saturate the articles to be dyed with a solution of ferric 
salt and ammonium oxalate (obtained by saturating oxalic acid 
with ammonium), to treat them next with prussiate of potash, 
and finally to pass them through a weak acid bath. Berlin blue 
prepared according to any of the above methods is entirely fast, 
and is not changed by acids, but is destroyed by alkalies. The 
coloring matter is, however, not soluble in water. With prus- 
siate of potash and a cupric salt, a beautiful brown is produced, 
the formation of which is due to the precipitation of cupro-ferric- 
cyanide upon the leather. 

Hed prussiate of p)oiash (potassium ferric-cyanide). This com- 
pound crystallizes in large, dark-red, monoclinic crystals soluble 
in water with a brownish-green color. It is poisonous. Its 
employment in dyeing is due to the fact that with ferrous salts, 



720 THE MANUFACTURE OF LEATHER, 

it yields a blue, the so-called Turnbull blue, which is similar, as 
regards behavior and appearance, to Berlin blue. It is an ex- 
cellent oxidizing agent especially in the aniline color industry, 
where it is chiefly used for the preparation of aniline black. 
For producing blue colors the cheaper yellow prussiate of potash 
is, however, to be preferred. 

It only now remains to mention in a general way the sub- 
stances which can be obtained by the action of alkalies upon fats 
and oils, and which are known as 

Soaps. 

The product of saponification, which is known as soap, must 
be classed with the salts. 

Soap of every kind, and especially that used in dyeing, which 
result from the saponification of a fat or oil by an alkali, must 
chemically be considered as a mixture, more or less pure, of the 
stearate, palmitate, and oleate of the alkali used, containing 
besides water and frequently an excess of alkali and some 
glycerine. 

Soaps are generally divided into potash and soda soaps accord- 
ing as the fat has been saponified with potash or soda. Potash 
soaps are generally soft and readily soluble in water, and soda 
soaps hard and more difficult to dissolve. A further difference 
in the quality of the soap depends on whether the soap is sep- 
arated by the addition of salt or prepared by simply evaporating 
the solution obtained by boiling the fat with the alkali. Soaps 
have the peculiarity of being precipitated from their solutions 
in water by an addition of common salt, and this peculiarity is 
taken advantage of, by throwing into the boiler a quantity of 
common salt, in order to separate the soap from the lye. The 
soap rises to the surface when the spent lye is drawn off" and 
the soap is brought into a solid form either by further boiling 
or by being transferred to iron moulds. Independent of the 
fact that such soaps are generally soda soaps, they have the 
. advantage of being purer than soaps not separated by salt, and 
are especially free from an excess of alkali. 

Generally speaking, good hard soda soap is the best to be used 
for dyeing purposes, it being only necessary to see that it is as 



DYEING LEATHER. 721 

white as possible and not too strongly alkaline. The variety 
known as Marseilles soap, which is a combination of olive oil 
and soda, and also the finer grades of white castile soap, can be 
especially recommended. A good quality of tallow soap or 
palm-oil soap can also be used with equal success. 

In dyeing leather soap is partly employed for preparing the 
skins to be dyed, and partly for giving lustre to the dyed 
leather. 



Section III. Mechanical Work of Dyeing Alumed 
Leather and Directions for Preparing and Applying 
Various Vegetable Dyes. 

Glove leather is dyed either upon the flesh side or upon the 
grain side. The latter process, which is the usual one, is ex- 
ecuted either by dipping or painting. 

In order to obtain uniform coloring the skins must in all 
cases be cleansed, ^. e., uniformly moistened by fulling in a drum 
or treading in lukewarm water. For this purpose the skins are 
placed in a vat with sufficient warm water to allow of their 
being thoroughly worked, and trodden with the bare feet of a 
workman, until they show no white spots. As by this treat- 
ment they lose a part of the egg substance and flour previously 
imparted with the tawing paste which has been .described in 
the preceding chapter, it is restored either only with yelk of 
egg (1 yelk for each skin) or with an addition of flour (100 
yelks of eggs and 2^ pounds of flour for one gross of skins). If 
several lots of skins are to be cleansed in succession, a saving of 
yelk of egg is effected by adding warm water to the liquor re- 
maining from the first lot and using it for treating the second 
lot, and so on. 

Dyeing the shins upon the flesh side, — After brushing whiting 
upon the flesh side the skins are smoothed with the hone. They 
are then cleansed, wrung out and after drying worked with the 
stretcher. The skin is then spread upon a table with a bed of 
zinc, such as is shown in Fig. 300, and the color applied as uni- 
formly as possible with a long bristled brush. Immediately 
after applying the color the skin while still moist is stretched in 
46 



722 



THE MANUFACTURE OF LEATHER. 



a frame and pumiced. In executing this operation the work- 
man holding the lower end of the skin with the left hand rubs 
with the right from top to bottom, pressing the pumice-stone as 
hard as possible upon the skin. After turning the skin and 
pumicing the portion not touched in the first operation, the skin 

Fig. 300. 




is dried in damp weather in a heated room. After drying and 
working with the stretcher it receives a second application of 
color and is again dried and worked with the stretcher. Should 
the color not be sufficiently intense, a third application is re- 
quired. 

The skins being already sufficiently mordanted by the alum 
contained in them, the only requisites for dyeing are simple decoc- 
tions of dye-woods, barks, and berries, such as logwood. Brazil- 
wood, Avignon berries, quercitron, etc., which are compounded 
for the different shades. A chestnut color is obtained by a de- 
coction of fungi, such as grow on the trunks of apple and yjear 
trees, prepared by breaking the fungi into small pieces, and 
after soaking them over night in water, boiling in water for two 
hours, and repeating the boiling in fresh water. 

To impart a black color the skins, after working them with 
the stretcher, receive a coat of iron liquor (acetate or methylate 
of iron) of about 2° B., and, after drying, a strong application of 
logwood decoction, and, finally, one of acetate of iron. Pumic- 
ing is omitted. To oxidize the iron the skins are exposed to 
the air for a few days and then brushed with a brush moistened 



DYEING LEATHER. 723 

with pure olive oil or almond oil, in order to give the black 
color the required lustre. To avoid spots, moisten the palm of 
the hand with the oil, and after passing it over the brush, take 
the oil from this brush with a second, and rub the oil into the 
skin with the latter. 

To prepare by this method of dyeing alumed leather, an imi- 
tation of Swedish leather, apply, after cleansing the skins, a 
color of oak bark, decoction of fungi, and Brazil-wood, and 
after giving yelk of egg, stretch, dry, and work them with the 
stretcher. Then apply the second coat of color, stretch, and 
work them with stretcher, and finally brush the leather upon 
the flesh side. 

Dyeing the skins upon the grain side. — For glazed leather 
and glazed glove leather the skins are first sorted into dif- 
ferent classes, the finest and whitest being reserved for white 
gloves, while the others are selected for light or dark colors, 
according to the cleanness of the grain. The skins are prepared 
in the same manner as those to be dyed upon the flesh side. 

Dyeing hy Dipping, 

To dye glazed skins by dipping, pour after cleansing and 
taking the skins from the vat, one- third of the dye-bath, the 
temperature of which should not exceed 77° to 86° F., into a vat, 
and work the skins in it with the hands to make the absorption 
of color uniform. Then beat them with the feet until the color 
of the bath is exhausted. After ten minutes remove the skins 
from the vat, and after pouring in the second third of the dye- 
bath, proceed in the same manner as before, and after that with 
the last portion of the dye-bath. Including cleansing, dyeing 
is accomplished in Icvss than an hour. The remaining dye-bath 
is poured into a vessel and used for another color. The dyed 
skins, after treating with yelk of egg, wringing out, swinging 
in the air, and stretching, are suspended by the lowest ends of 
the hind shanks, and quickly dried. 

As the flesh side is also dyed by dipping, this process is gene- 
rally only used for delicate and light colors. Berries are still 
often used as a dye-stuff'. For yellow Avignon berries, for gray 
dwarf elderberries, for sea-green privet dog-wood berries, and 



724 THE MANUFACTURE OF LEATHER. 

for Other green shades buckthorn berries. Yery dilute decoc- 
tions of dye-woods are also used. For canary-yellow weld, for 
rose color Brazil-wood, for lilac logwood, and for other shades 
mixtures of these decoctions. A peach color is, for instance? 
prepared by boiling 1 pound 2 ounces of Avignon berries, 2^ 
ounces of ground Brazil-wood, and 1 pound 2 ounces of dwarf 
elderberries in 21 pints of water for two hours. It is not ad- 
visable to use astringent substances, such as quercitron, sumach, 
oak tan, etc 

Dyeing ly Painting. 

Dyeing glazed leather by painting can be accompl'shed either 
according to the Grenohle or the English method. 

By the Grenoble method the skins are first cleansed, i. e., soaked. 
After removal from the cleansing water they are placed upon a 
smooth board and smoothed with a horn tool, so that they lie 
closely to the board, and then brushed to remove any adhering 
dust, etc. After the skins have become dry, three or four coats 
of color are applied in succession, and the skins allowed to 
dry upon the boards. When dry they are taken from the 
boards, put in a damp place and worked with the stretcher. 
Lixiviated boards of linden wood joined with glue compounded 
with linseed oil are used for the purpose. After use they are 
thoroughly washed with water, or, if necessary, with weak lye 
or diluted acid. Every time before being used they must be 
painted with a decoction of flaxseed, this promoting partly the 
clinging of the skins to the boards and protecting them from dirt. 

The colors used are as a rule the same as used for dyeing by 
dipping. 

For violet apply a gray ground with dwarf elderberries and 
upon this a decoction of logwood. Chamois and nankin are 
obtained with Avignon berries and Brazil- wood; hazel-color by 
an addition of dwarf elderberries, and chestnut color by a further 
addition of logwood decoction. For olive-green apply lirst a 
mordant of acetate of iron or copper, and then a color prepared 
from Hungarian yellow berries with more or less logwood 
decoction, etc. For black a decoction is used prepared for 1 
gross of skins, by boiling 2 pounds 3 ounces of Hungarian yel- 



DYEING LEATHEE. 725 

low berries, 2 pounds 3 ounces of sumach, 11 pounds of logwood 
in 4| to 5| gallons of water until reduced to one-half the quan- 
tity. After filtering apply the fluid to the skins, and when dry 
give a coat of liquor of acetate of iron of 2° B,, and repeat the 
alternate application twice more. When the skins are thoroughly 
dry, wash them with a brush and water, and then work them 
with the stretcher. Should the color be wanting in intensity 
give another coat of logwood decoction only. After drying, a 
lustre is imparted to the skins by brushing them with a strong 
solution of white soap into which the yelks of a few eggs have 
been stirred. A good lustre is also obtained by using a mixture 
prepared for 6 dozen skins, by boiling 10| ozs. of soap, 1^ ozs. 
of lard, and If ozs. of soda in a sufficient quantity of water, and 
adding a decoction of 10| ozs. of flaxseed. After polishing, the 
skins are rubbed with a woollen rag and worked once more with 
the stretcher. 

The English method^ which is now generally used, has the 
advantage of furnishing more durable colors than the other 
methods, though very delicate shades such as by dipping can 
only be produced with difficulty or not at all. The process con- 
sists in giving the skins first a ground with a potash solution 
and applying upon this the dye liquor. Firing required for 
some colors is effected by an application of green vitriol. The 
principalobject of the alkaline ground is that by preventing the 
dye-liquors from penetrating, a greater saturation of the surface 
with dye is effected, which may possibly be due to the decom- 
position of the free alum still present in the skins. The mode 
of executing the process is as follows : — 

After cleansing and moistening the skins in warm water until 
they show no white spots, the water is poured off' without wring- 
ing the skins. Then take one yelk of egg for each skin, stir all 
the yelks together with some warm water, and after pouring the 
liquid over the skins, beat with the feet until all the egg sub- 
stance has been absorbed. Then take each skin separately from 
the vat, and, after rinsing thoroughly in cold water, spread it 
upon a table so that it has no wrinkles. The table is somewhat 
higher on the end where the workman stands, and is provided 
with a zinc top and a ledge open on the lower edge where the 



726 THE MANUFACTURE OF LEATHER. 

fluid runs off. The spreading out of the skin is effected with a 
tool of horn. 

The alkaline mordant consisting for dark colors of a solution 
of 1 part of ordinary blue potash in 15 parts of water, and for 
light colors of 1 part of potash in 30 parts of water, is then 
applied with a brush. Instead of the potash solutions, solutions 
of 1 part of soda in 10 parts of water or 1 part of soda in 25 
parts of water may be used. After applying the solution 
quickly and smoothing out the wrinkles, a second coat is given. 

The thoroughly cooled dye is then immediately applied with 
a somewhat stiff'er brush than is used for laying on the ground. 
The work should be done as quickly and uniformly as possible. 
Eubbing with a full brush upon one spot must be avoided. 

After applying the color, the skin is washed upon the table 
with well water, and then smoothed to remove the wrinkles. 
Applying color and washing is repeated until the water runs off 
clean. For colors requiring firing, a solution of y^ths to 1 oz. of 
Salzburg green vitriol and 4:^ to 5^ pints of water is applied after 
the second coat of paint and washing. Paint the skin thoroughly 
and uniformly with the solution, and, after allowing it to soak 
in somewhat, proceed with the washing with well water and 
smoothing as before. 

French Method. — In France a somewhat more alkaline mor- 
dant is used. It is generally composed of one quart of old urine 
which has become oily, 1\ ozs. of sodium carbonate, and 2 small 
liqueur glasses full of liquid ammonia. By applying this mor- 
dant carefully a beautiful yellow color is obtained with fustic 
of prime quality. By adding a little red to this color, chamois 
is produced, and orange-yellow by increasing the proportion of 
the red color with an addition of some Avignon berries. Hazel- 
nut and chestnut-brown are obtained by adding more red and 
some violet. 

Before proceeding with the dyeing the skins are sorted ac- 
cording to the colors for which they are best adapted. The 
best quality is used for light brown, mixed brown, olive-brown, 
sap-green, and olive-green ; the medium for lemon color, orange, 
violet, dark brown, dark gray, and nankin color; and the poor- 
est for dark green, iron gray, and black. 



DYEING LEATHER. 727 

With the exception of spirituous tinctures, which can be kept 
in well-stoppered bottles, it is best to mix the colors fresh and 
use them immediately after cooling. Scrupulous cleanliness 
and order should prevail everywhere. The cloth or sieve for 
straining the color, the vessels for the latter, the brushes, and 
especially the dye-table must be kept as clean as possible. 

The mechanical portion of the dyeing of alum leather is 
divided, according to the French method, into five parts : — 

1st. The assorting of the skins into the different colors and 
shades, and if for gloves into ladies' and gentlemen's. 

2d. The washing, cleansing, that is to say, the preparation of 
the skins for dyeing. 

3d. The dyeing itself (a) on the table ; grain and flesh dyeing 
(b) by dipping the whole skin in the dye liquor; viz. : plonge, 
suede. 

4th. The drying of the dyed skins. 

5th. " Boarding" the same ; that is, to render the dyed and 
dried skins soft and smooth again. 

The first thing to do is to assort the skins into the different 
classes, as it is impossible to take alum skins and dye them 
just as they run. 

Into the first class we put all the skins of a very fine grain, 
the smoothest and freest from air, lime, or iron spots. On these 
skins there can be dyed shades such as Havana, Bismarck, Bore, 
light chestnut, or leather brown, light terra-cotta, old gold, steel 
gray, mais, etc. 

The second class embraces skins on the grain of which we 
can recognize the marks left from the black hair of the living 
animal. Such skins are reserved for light chocolate, brown, 
medium olive, smoke gray, Eussian green, dark terra-cotta, Car- 
melite, etc. 

The third class consists of skins on which the alum or salt, 
while drying after tawing, has formed a kind of a marbled 
face ; skins with a partially open or coarse grain. On these 
skins there is usually set a dark olive color or bronze, dark 
grays, bottle-green, or black; also the very dark brown; in 
general such shades in the composition of which an iron salt is 
used, such as sulphate of iron, as a striker. 



728 THE MANUFACTUEE OF LEATHER. 

The fourth class of skins are those the grain of which is too 
much damaged. These skins should be dyed on the flesh side 
(undressed kid), provided this part of the skin proves consistent 
enough in its structure to support the emery wheel or pumice- 
stone, in order to give it an even velvet-like face. 

When the skins are thus selected, mark each class on the 
neck with a little cut ; the first class with one cut, the second 
class with two cuts, etc., so that they can be recognized again 
should the whole lot be washed together in a drum or tub. 
The dyeing of alum leather is a very unthankful task. Even 
with the greatest care the skins often do not turn out as they 
ought to do. But one thing is certain, if we are not very care- 
ful, as in this case, our work is condemned beforehand, and we 
must not wonder if we spoil the skins or produce uneven 
dyeing. 

We entered upon a full explanation of the assorting and pre- 
paring of the skins for dyeing, because it is, so to say, the prin- 
cipal operation of the dyeing itself; on badly-prepared skins, a 
dyer cannot set an even color. 

Suppose the skins we assorted belong altogether to the first 
three classes, that is to say, they are skins to be dyed on the 
grain and in fancy colors. We marked the different classes 
with little cuts at the neck; now that they are washed, we have 
to assort them again. On class No. 1 we will set a leather- 
brown; class No. 2 we will dye in a medium olive; of class No. 
3 we will dye one-half of the lot chocolate-brown, and the re- 
maining skins bottle-green. 

In the morning, while the brusher (that is, the man perform- 
ing the mechanical work of dyeing the skins) is cleaning the 
dye table, bowls, dye brushes, and assorting the prepared skins 
into the different classes again, the head dyer is preparing and 
mixing the colors. For this purpose, he needs the so-called 
mother dye-liquors — red, yellow, and blue. If it is not advisable 
to prepare the dye liquors by boiling the dyewood chips our- 
selves, which preparation requires at least three hours' boiling, 
it may be equally as good to have the extract of such dyewoods 
on hand, in which case the boiling lasts only a quarter of an 
hour. Many dyers say they cannot depend on the extracts of 



DYEING LEATHER, 729 

dyewoods. This Avas probably true before we bad the improved 
machinery to produce good and pure dyewood extracts. 

In preparing the three mother dye liquors, the dye stuff's 
used for this purpose are : For No. 1, extract Brazil-wood 
{Ceesalpinia christa); for No. 2, extract fustic {Morus tinctoria)] 
for No. 3, extract logwood [Hsematoxylon campeachianum). 

To prepare the Brazil-wood mother dye liquor, put 20 gallons 
of clear water in a copper kettle, if boiled by open fire, or in a 
wooden tub or barrel if boiled by steam. To produce a strong 
dye liquor, 5 pounds extract Brazil-wood are allowed to boil for 
about 10 minutes. After this time add, always under stirring, 
one ounce of potash and one ounce of soda, in small quantities, 
and continue to boil it for 5 minutes longer. Now this mother 
dye liquor is ready, and must be drawn off' in a separate barrel 
and covered. 

The fustic mother dye liquor is prepared exactly in the same 
way, the same quantity of water, dye wood extracts and chem- 
icals being used. 

For the logwood mother dye liquor, use onlj^ 4 J pounds ex- 
tract for 20 gallons of water. To this add 1 gallon old urine. 
After boiling 10 minutes, add 1 ounce soda and 2 ounces potash, 
and continue to boil for 5 minutes. Then the liquor is drawn 
off' into a barrel and ready for use. 

Clean the kettle or tub thoroughly after each color is boiled, 
so that one color will not interfere with the following one. 

Besides these mother dye liquors, there are also required the 
so-called strikers. These are solutions of metallic salts, mostly 
sulphates. To dye our intended four shades we need three of 
them : striker No. 1, alum 3 pounds dissolved in 40 gallons of 
water ; striker No. 2, sulphate of copper, 3 pounds, dissolved in 
40 gallons of water; striker No. 3, sulphate of iron, 1 pound, 
dissolved in 40 gallons of water. 

Now that the skins are ready for dyeing, the mother dye 
liquors and strikers prepared, we can proceed to compose our 
shades. The first is — 

Light-Leather Brown. — Take fustic dye liquor 12 gallons, 
Brazil-wood dye liquor 1^ gallons, logwood dye liquor 3 quarts. 
Use striker No. 1. The second shade is — 



730 THE MANUFACTURE OF LEATHER. 

Olive. — Take fustic dje liquor, 6 gallons, logwood dye liquor 
6 gallons, Brazil-wood dye liquor \ gallon. Use striker No. 2, 
The third shade is — 

Mi-fonce Brown. — Take fustic dye liquor 4 gallons. Brazil- 
wood dye liquor 6 gallons, logwood dye liquor 4 gallons. Take 
striker No. 2 and striker No. 3 in equal proportions; mix well 
and use. The fourth and last shade is — 

Bottle Qreen. — Take fustic dye liquor 4 gallons, logwood 8 
gallons. Use striker No. 2. 

The dye is applied with a suitable brush. The hair of such 
a brush should be pretty stiff, and about 1| inches long, so that 
it may hold a proper quantity of dye liquor by dipping it in 
the bowl which is placed on the sideboard near the dye table. 
The wet skin is spread on the table which is shown in Fig. 300, 
flesh side down, and stretched out with a wooden or rubber 
" slicker." The skin must, of course, lie evenly on the table, so 
that no fold can be seen. Now apply consecutively two brushes 
full of old urine on the skin, brushing with each brush full of 
liquid two or three times around the skin. It is unnecessary 
to say that, for the urine (mordant), as well as for the dye 
liquors and strikers, an extra brush is used. Never change the 
brushes, nor use a dye liquor brush for striker, or vice versa. 
After the mordant is applied to the skin, put the color on it 
immediately. Each skin must be brushed four times at least, 
taking each time a good brush full of dye liquor (or two if 
necessary), brushing the skin on all its parts for about one and 
a half minutes with each brush full of dye liquor. In brushing 
the skin, while dyeing it, it is necessary to be quick, always 
trying to keep the dye liquor as much as possible on the surface 
of the skin. The weak part of the skin, as for instance the 
flanks and the neck, where the dye does not take very well, 
should be brushed a little more than the middle of the skin, that 
is, the back. 

The method of brushing the dye liquor on the skins is indi- 
cated in Fig. 301. 

A dyer should never commence to dye a lot of skins before 
being certain that everything is right. Consequently it is best 
to dye one of the prepared skins in the regular way with the 



DYEING LEATHER. 



'31 



dye liquor prepared for the whole lot of skins; dry it and 
stretch it out, in order to see the shade and compare it with the 
sample, so that we may discover the error, if there is any, and 
correct it. Then, but then only, the brusher can continue to 



Fiff. 301. 





dye the whole lot. The imitation on paper of these shades is 
not quite so nice as are the leather samples. On leather, of 
course, these shades appear fuller, that is to say, better nour- 
ished. 

After the skin is well nourished with dye liquor, put the 
striker on it. This striker it is convenient to have also in a 
bowl on the table, so that it can be reached when required. 
Two brushes full of striker applied in the above-mentioned way 
are sufficient for each skin. Now the skin is dyed and ready to 
be rinsed with water out of a barrel kept near the table — 
that is to say, a dipper full of water is poured over it ; then turn 
the skin flesh side downward and drive all the superfluous water 
out of it by means of a copper slicker. After this take the skin 
from the table and hang it up, clean the table with water and 
recommence the same manipulation with another skin. As 
soon as four skins are dyed, hang them up in the dry-room or 
in the open air, in the shade, as the wet skins must never be 
hung in the sun. 

When the skins are dyed and dried they appear hard and 
stiff' and require to be softened again. For this purpose lay them 
in damp pinewood sawdust, in pairs, with the grain inside, so 
that the sawdust touches only the flesh side of the skins. When 
they have absorbed sufficient dampness, take them out of the 



732 



THE MANUFACTURE OF LEATHER. 



sawdust and press them in a basket. Now they are ready to 
be " boarded," that is to say, softened again. If the skins which 
it is desired to soften are not damp enough, it will be hard work 
to soften them perfectly; if, on the contrary, they are too damp, 
there is the risk of cracking the grain while boarding them. 

After the skins are softened they are, of course, too damp to 
bring into the market. It is necessary then to hang them up, 
in order to get rid of the dampness. When entirely dry overlet 
them on the board again — that is to say, pull them in the length 
and width, to get rid of any hardness remaining, occasioned by 
the last drying. After the manipulation of overletting, the 
skin must stay altogether in the width, not in the length, and 
it is in this shape that they are in condition to go into the 
market. 

Fig. 302. 




The French knee contrivance employed for " boarding" or 
softening, and overletting the skins is shown in Fig. 302 ; the 
armboard is shown in Fig. 243. 

Section IV. Receipts for Various Vegetable Colors, and 
FOR Coloring Leather with Mineral Pigments. 



We give in the following a number of receipts taken partly 
from PrechtVs " Technological Encyclopedia^'''' a work which, 
though somewhat old, contains many valuable items. 



DYEING LEATHER. 733 

Dark hroion. — Boil 8 parts by weight of Hungarian fastic, 1 
part of logwood, 2 parts of Brazil-wood, 1 part of sandal-wood, 
and I part of quercitron in sufficient water to cover the ingre- 
dients about 2 inches deep, for 1 hour. Strain the liquor 
through linen, and when cold use for dyeing after an application 
of green vitriol. By boiling the ingredients with water for a 
second time, the resulting decoction can be used for a similar 
color. 

Light hroiim. — By applying a thin ground of potash solution 
and omitting the coat of green vitriol, the above color can also 
be used for this. 

Olive-hroion. — Boil as above 2 parts of Hungarian fustic, 1 
part of quercitron, and \ part of logwood. Apply the color 
upon a strong ground of potash solution, and then give a coat 
of green vitriol. 

Catechu hroiun. — Apply a decoction of 1 lb. 2 ozs. of catechu 
in 10| gallons of water, and 2 ozs. of green vitriol to the slightly 
grounded skins. 

Catechu gray-hrown is obtained with the above color and an 
after application of solution of green vitriol. 

Coffee hrow7i. — Apply to the moist skin a ground composed of 
a solution of 2| lbs. of acetate of copper in 13|- gallons of water, 
and after draining, wet immediately with a solution of yellow 
prussiate of potash in slightly acidulated water. 

DarJc green. — Apply a decoction of 4 parts of quercitron and 
1 part of logwood upon a strong ground with an application of 
green vitriol. Some dogwood berries may be added to the 
decoction, and for fining a like quantity of blue vitriol to the 
green vitriol. 

Olive green. — Decoction of 2 parts of quercitron, 1 part of 
Hungarian fustic, and some dogwood berries. Apply upon a 
strong ground. Omit the vitriol. 

Light olive green. — Give the skins a light ground with Berlin 
blue, and apply upon this a liquor obtained by boiling 2^ lbs. of 
fustic, and 10| ozs. of archil in 5 J gallons of water. 

Picric green. — Apply a solution of picric acid in water to the 
skins previously grounded with Berlin blue. 

Lemon color. — After digestion 1 part of turmeric in i parts of 



734 THE MANUFACTURE OF LEATHER, 

ordinary spirit of wine at a moderate heat or in the sun for 24 
hours, and diluting with ordinary whisky apply the mixture 
uniformly with a clean sponge kept especially for this purpose. 
After drying upon the boards rub the skins with a woollen rag 
dipped in Spanish chalk, without previous application of a coat 
of green vitriol. 

Quercitron yelloio is obtained in various shades by applications 
of decoctions of quercitron bark. 

Barberry yellow. — Apply a liquor obtained by boiling 2| lbs. 
barberry root and 7 ozs. of alum in 8 gallons of water. 

RustyelloTu. — Apply a composition obtained by boiling 2^ lbs. 
of annotto, 7 ozs. of soap, and 4 ozs. of potash in lOJ gallons of 
water. 

Orange. — Digest 1 part of Brazil-wood shavings in 8 parts of 
spirit of wine, and after diluting with whisky add more or 
less of the above lemon color. Apply the mixture to the slightly 
grounded skin, omitting the application of green vitriol. Orange 
is also obtained with annotto and decoction of madder. 

Violet. — Digest 1 part of dry shavings of logwood in 8 parts 
of spirit of wine, and after diluting with whisky, treat the 
slightly grounded leather as above. 

Mixedhrown. — A beautiful brown of various shades is obtained 
by mixing different proportions of the three foregoing colors : 
lemon color, orange, and violet. Apply upon a slight ground 
without an application of green vitriol. A darker color is 
obtained by repeating the application. 

Sap green. — Digest 1 part of buckthorn sap in 4 parts of spirit 
of wine, and apply upon a slight ground in the same manner as 
given for lemon color, omitting the application of green vitriol. 

Nankin yellow. — Digest 1 part of madder in 4 of spirit of wine 
and apply in the same manner as lemon color, without applica- 
tion of green vitriol. 

Dark blue. — Use a concentrated decoction of logwood upon a 
strong ground without application of green vitriol. A better 
and faster blue is obtained by applying a solution of indigo 
carmine. 

Red. — A magnificent shade of red is obtained by an applica- 
tion of cochineal color prepared by tying the cochineal in a 



DYEING LEATHER. 735 

small linen bag and boiling in water to wliicli has been added 
about 2 per cent, of spirit of sal ammoniac. 

Alazarine red {a pale flesh color) is produced bj rubbing the 
cleansed and trodden skins with a solution of alazarine or ex- 
tract of madder in weak soda lye and rinsing in water. 

Scarlet is produced by an application of extract of carthamus, 
especially upon skins with a weak annotto ground. The ex- 
tract of carthamus is dissolved in a solution of 1 part of tartaric 
acid in 60 parts of water. 

Red of any other shade is obtained by applying spirituous 
extract of sandal -wood upon a weak ground. 

Dark gray. — Decoction of 1 pound 2 ounces of Indian fustic, 
9 ounces of tan-liquor and ^ to | ounce of concentrated decoc- 
tion of logwood. Apply upon a strong ground and give a coat 
of green vitriol. 

Iron gray. — 9 ounces of tan-liquor, 2^ pounds of solution of 
green vitriol, and |- to jounce of logwood extract. Apply upon 
a strong ground, omitting the application of green vitriol. 

Black. — Boil 1 part of logwood and | part of quercitron for 
two hours. Apply upan a strong ground and follow with an 
application of green vitriol. A black color is also obtained by 
boiling, for one dozen small skins, 2J pounds of logwood, 21 
ounces of fustic, J ounce of Hungarian yellow berries, J ounce 
of pulverized gall-nuts and 1 ounce of sumach in 8 gallons of 
water for two hours, or until reduced to about one-half the 
quantity. Apply upon a strong ground and follow with an 
application of green vitriol. 

A lustre is imparted to the leather by the process previously 
given. 

Mineral Pigments. 

Leather may also be colored by mineral pigments. The 
color is more durable and resists air and moisture better than 
that obtained with vegetable coloring matter, but the process is 
more troublesome on account of the difficulty of obtaining a 
uniform coloring. 

The manner of execution is essentially the same as in calico 
printing. The skins, after cleansing and wringing out, are 



736 THE MANUFACTUEE OF LEATHER. 

placed upon the board, and the respective dye-solutions applied. 
Thus sky-blue is obtained by first applying a thick coat of 
solution of 9 pounds of yellow prussiate of potash in 16 gallons 
of water so that the skin is thoroughly permeated, and then a 
weak solution of acetate of iron, containing not more than ^ to 
^ ounce of the salt to one quart of water. 

Brown is obtained by using, instead of the iron solution, one 
of acetate of copper. Before applying the solution of yellow 
prussiate of potash it is made slightly alkaline by adding 
potash. 

Chrome yellow is produced by applying a thick coat of a 
solution of one ounce of red calcium chromate in one pint of 
water, followed by an application of a solution of one ounce of 
sugar of lead in one pint of water. 

Section Y. Dyeing Chamois or Oil Leather. 

The dyeing of this variety of leather differs from that of 
alumed leather in being executed almost exclusively by dipping, 
and the skins generally requiring to be treated with a mordant 
before applying the color. 

The process is as follows: Skins to be dyed a light color are 
first exposed to the sun, and then uniformly moistened by tread- 
ing in lukewarm water in the same manner as given for alumed 
leather. The skins are then placed and thoroughly worked in 
a warm mordant composed, for 20 skins, of a solution of 2 J 
ounces of alum and ^ ounce of tartar in about 20 times the 
quantity of water. After thorough soaking and slightly wring- 
ing out, the skins are immediately passed first through a weak 
dye-bath, and after wringing out, through a more concentrated 
one, the process being repeated until the desired shade is ob- 
tained. After thorough wringing out, the dyed skins, especially 
those intended for glove leather, are treated with a paste of 
alum and yelk of egg, shaken out, dried, and finally worked 
with the stretcher. 

As oil or chamois leather is, as a rule, used for articles to be 
washed, it is of course self-evident, that only fast colors can be 



DYEING LEATHER. 737 

used in dyeing. We will here briefly discuss the most impor- 
tant coloring matters used in this branch of the industry. 

Madder red upon oil leather is obtained in the following man- 
ner : Dissolve, for every 10 to 12 skins, 2 pounds and 3 ounces 
of white sugar, and 13 pounds of alum free from iron in the re- 
quired quantity of water, and add 4z\ pints of spirit of wine, 
and tread the skins in the solution for 2 hours. Before sub- 
mitting the skins to the process, they should be thoroughly 
fulled with lukewarm water and washed with boiling water, 
and after passing through dilute sulphuric acid (1 part to 60 
parts of water) subjected to a final washing. After working the 
skins thoroughly in the solution, remove them from the vat and 
after slight wringing, draining off", and rinsing in water, dry 
them in the shade. After partial drying replace them in the 
same bath, to which in the mean while some warm water and 
about one quart of spirit of wine have been added, and allow them 
to remain for one hour with occasional working. After the skins 
b}^ repeated wringing out and replacing in the bath have been 
thoroughl}^ soaked through, and passing them once more through 
the bath, spread them in piles upon a table for 2 to 3 hours. 

The skins thus prepared now receive the actual mordant for 
madder red. This is prepared by mixing 20 pints of the above 
mordant with one pint of tin composition and 20 gallons of 
water. After stirring the mixture thoroughly, full or tread the 
prepared skins in it for one hour. After removing and allow- 
ing to drain off beat and roll them upon a smooth stone for some 
time, drav^^ing them from time to time through the mordant. 
Then hang the skins up in the shade to dry, and when air-dried 
place them in a room heated to 86° F., where they should re- 
main for at least 12 hours. The skins are then ready for dye- 
ing. After taking them from the drying-room rinse them first 
in cold water, and after fulling in cold water, air and rinse them 
once more. To obtain a better color they are frequently trod- 
den, before actual dyeing, in a bath composed of If to 2 ounces 
of madder and 26| gallons of water. 

The madder bath is prepared by adding 8f pounds of good 
madder to 37 to 42 gallons of water in a boiler and heating 
gradually to a temperature not exceeding 118° to 122° F. 
47 



738 THE MANUFACTURE OF LEATHER. 

Place the skins in the bath one by one, and after allowing them 
to remain until the above temperature is reached, 5 to 6 hours 
being generally required, place them at once in running water, 
and after thorough rinsing and repeated fulling upon the stone 
hang them up to dry. 

In order to give the dyed skins more lustre, they are placed 
in the fining bath prepared by mixing 26| gallons of water, J 
pint of spirit of wine, and ^ pint of olive or almond oil. After 
treading the skins thoroughly in this bath, rinse once more 
and dry. A solution of 2 pounds and 3 ounces of soap in 13^ 
gallons of water may be used in place of the above fining bath. 

Blue in all shades is obtained upon oil leather by dyeing in the 
indigo vat. The skins require no special mordant for this, but 
must, like for all other colors, be thoroughly trodden in water 
and moistened. Oil leather not thoroughly cleansed from free 
oil or- fat, will not take the color uniformly, and must before 
dyeing in the vat be passed through a bath composed of 1 part 
of potash and 15 parts of water, and rinsed. 

Green upon oil leather is obtained either by dj^eing the skins, 
after giving them a ground in the blue vat, in decoction of 
quercitron, or, according to the old method, Avith buckthorn 
berries. The following receipt will answer for the latter pur- 
pose : Dissolve, for 12 dozen skins, 2 pounds and 3 ounces of 
green vitriol and 1 pound and 2 ounces of alum in 8| pints of 
water, and after adding 1 pint of this solution to the warm 
water required for treading the skins, work them thoroughly. 
After wringing, place them in a fresh bath of warm water some- 
what colored with a decoction of 26J pounds of quercitron bark, 
8| pounds of logwood, and 2 pounds and 3 ounces of Hun- 
garian yellow berries. After treading them in this, replace 
them in the first vat, charged in the mean while with fresh water 
and some green vitriol. Tread them in this for some time, then 
replace them in the second vat, containing fresh water with a 
larger addition of the above decoction, and beat thoroughly 
with the feet. This process is repeated three or four times, 
adding every time an increased quantity of green vitriol and 
decoction. To the last dye bath add a decoction of ripe buck- 
thorn berries, or the commercial sap green, increasing the quan- 



DYEING LEATHER. 739 

tity, with vigorous stirring, until the desired shade of green is 
obtained. The skins are then allowed to drain off, and finally 
placed in a mordant, prepared by dissolving 6 ounces of ace- 
tate of copper in the required quantity of water. Rinse the 
skins thoroughly in the solution, and after rinsing in cold water 
dry them slightly in the air. To restore softness to the dyed 
skins, tread them in a mixture of 100 yelks of eggs, 1 pound 
and 2 ounces of alum, and the necessary quantity of water, and 
after wringing and drying work them with the stretcher. 

Yellow. — This color if not produced with yellow ochre is 
obtained by means of a decoction of quercitron and previous 
mordanting with alum. Chrome yellow is seldom used. The 
latter color, which makes the leather weighty, can be best applied 
as has been described under mineral pigments. For this purpose 
the skins to be dyed are first thoroughly failed in a bath of sugar 
of lead, and then thoroughly worked in a bath composed of 1 
part of potassium chromate and 8 to 10 parts of water. The}" 
are next rinsed and dried. 

Brown upon oil leather can be obtained by using the catechu 
bath mentioned for alumed leather. A beautiful red-brown is 
produced by dyeing the leather previously mordanted with 
acetate of copper, in a solution of yellow prussiate of potash 
and final rinsing in dilute acid. This brown is very fast and in 
many respects preferable to one produced by decoction of fungi, 
etc. 

Black upon oil leather is conveniently produced in the 
following manner : After moistening the skins uniformly, 
apply to the side to be dyed a decoction prepared by boiling 10 
parts of logwood, 10 of sumach, 2 of pulverized gall-nuts, and 
2 of quercitron bark, in about 60 parts of water until reduced 
to one-half the quantity. Spread the moistened skins one over 
the other and apply the decoction to each one in succession 
with a soft brush. After all the skins have been brushed over 
give a second coat, commencing in the same manner, and finally 
a third one which will generally be sufficient. Next apply to 
the prepared skins two coats of black liquor, and when this is 
absorbed, a coat of the decoction, and upon this, if necessar}^, a 
third coat of black liquor. To obtain an intense black give a final 



740 THE MANUFACTUEE OF LEATHER. 

coat of pure decoction of logwood. To give lustre to the dyed 
skins, brush them lightly over, after drying, with olive oil in 
the same manner as alumed skins. To make the leather more 
salable it is recommended to black the uncolored side. 

Section YI. Dyeing with Analine Coloes and the 
Methods of theie Peepaeation. 

Having given in the foregoing sections of this chapter the 
iKiiOst important methods of dyeing formerly in general use and 
stj.ll ,so in some places at the present time, it remains to give 
the process of dyeing with aniline colors. 

Aniline colors, excepting the actual rosaniline colors, are espe- 
cially suitable for coloring leather partly on account of their 
brilliancy of color frequently combined with a high degree of 
fastness, and partly on account of their being absorbed with 
avidity by the leather substance. A special mordant to prepare 
the leather for the reception of the coloring matter is but seldom 
required, a simple application of the color either in aqueous or 
spirituous solution being generally sufficient. Colors which can 
be used in aqueous solution are, as a rule, preferable to those 
only soluble in ethyl or methyl alcohol, especially as alumed 
leather will not stand strong alcoholic solutions. If colors only 
soluble in alcohol have to be used, care should be had to dilute 
the dilution with as much water as it will bear without sepa- 
rating the coloring matter. It is of course self-evident that the 
dyeing with aniline colors can be accomplished in the same 
manner as with other dye stuffs either by dipping or painting, 
though the latter method is with few exceptions to be preferred. 
If it should happen that the leather will not take an aniline 
color or does not dye uniformly, recourse must be had to a 
mordant. The most convenient and effective method of mor- 
danting leather for aniline colors, is to apply a ground with a 
fluid containing tannin, it being of course necessary to use a 
composition which will not color the leather perceptibly. The 
best plan is to apply a solution of ] part of tannin (pure gallo- 
tannic acid) in 20 to 25 parts of water with a sponge. After 
partly drying the leather apply the first coat of color, using a 



DYEING LEATHEE. 741 

weak solution, and stronger ones for the succeeding coats until 
the desired shade is obtained. For dark colors, such as orange 
yellow, brown, or even green, a cheaper solution containing 
tannic acid will answer the purpose just as well, a weak decoc- 
tion of sumach being especially suitable. In using an aqueous 
solution of picric acid, which is also very good for giving a 
ground to leather to be dyed with aniline colors, the fact that 
the shade of the latter is frequently changed must be taken 
into consideration. A fast black can be produced with aniline 
colors, and in this and the next chapter we shall give the dif- 
ferent modes in which it is accomplished. 

Oil or chamois leather can also be dyed in the same manner 
as aluraed leather with aniline colors, without requiring special 
preparation. Beautiful brown and blue colors can especially be 
produced with aniline colors, but for red it is better to use the 
process for madder red, as the color obtained with fuchsine or 
coralline, though very brilliant, is not particularly fast. 

Aniline colors are especially valuable for dyeing parchment, 
since brilliant colors can be obtained without the parchment 
losing its transparency as is the case with other dye stuffs, 
especially such as require a mordant. 

Aniline Violet. 

Perldns's violet in a pure state is either a dark violet paste, 
or, what is more frequently the case, a dry green crystalline 
powder of a metallic lustre. It is but moderately soluble in 
cold water but readily in hot, and also, in the presence of an 
acid, in alcohol, wood spirit, glycerine, acetic acid, etc. From 
its solutions it is precipitated by alkalies and alkaline salts, and 
from spirituous solutions by water. 

Parisian violet is insoluble in water, but dissolves readily 
by adding an acid. 

Hofraann's violet, pre-eminent on account of its purity and 
beauty, is but moderately soluble in water but readily in alcohol, 
wood spirit, etc. In commerce, Hofmann's violet, of which 
there are two varieties, a reddish violet and a blue violet, occurs 
in bronze colored grains or crystals. 

Rosaniline violet \q a brownish blue powder with a weak lustre. 



742 THE MANUFACTUEE OF LEATHER. 

and is scarcely soluble in water but readily in alcohol and acetic 
acid. 

Dahlia (dahlia imperial) is probably a by-product obtained 
in the manufacture of aniline red. It is a beautiful violet color- 
ing matter of rare purity of color and is readily soluble in hot 
water. It differs from the ordinary aniline violet in assuming 
a brownish-red color when treated with concentrated sulphuric 
acid while the latter is colored blue. , 

Aniline Blue. 

Bleu de Paris (soluble aniline blue) is a black-blue powder 
with a slight copper lustre. It is soluble in water, and may be 
precipitated from its aqueous solution with acids or common 
salt. This blue, on account of its solubility in water, may be 
especially recommended for coloring leather. 

Bleu de Lyon. — This color does not differ chemically from 
the foregoing. It is difficult to dissolve in water, but readily in 
alcohol, and gives a beautiful blue color. It comes into com- 
merce in lustrous masses of a copper-red color. 

Ordinary aniline blue (also rosaniline blue) is insoluble in 
water, but soluble in alcohol, A¥Ood spirit, etc. It is also solu- 
ble in concentrated sulphuric acid, and can be precipitated in an 
unaltered state from such a solution prepared cold, by an ad- 
dition of water. But by heating a solution in concentrated 
sulphuric acid to 266° to 284° F., even for a short time only, 
the blue precipitated by an addition of water and washed, is 
entirely soluble in boiling water. There are two principal 
shades of this aniline blue, the bleu de lumih^e^ which shows a 
pure blue color by candlelight, and a darker blue, bleu de Parme, 
with a violet tinge and having a difi'erent color by candle- 
light. 

Aniline Green. 

Aldehyd green (rosaniline green) occurs in commerce either 
in the form of a paste or as a green powder. The article in 
paste form is the picrate of a base which has not been much ex- 
amined. The paste is not soluble in water, but in alcohol and 
acids, while the powder dissolves in boiling water. 



DYEING LEATHER. 743 

Ethyl rosaniUne green dissolves with difficulty in water bat 
readily in alcohol. 

Emeraldine, a green patented in England by Calvert, Lowe, 
and Clift, is insoluble in water, alcohol, and acids, but dissolves 
with a blue color in concentrated sulphuric acid. It is constant 
in the light ; but it is difficult to utilize it for coloring leather. 

Aniline Yelloio. 

Ordinary aniline yelloio is scarcely soluble in cold water but 
readily in alcohol, wood spirit, etc. 

Zinaline is found in commerce in the form of a cinnabar- 
colored powder, which is insoluble in water but dissolves in 
warm solutions of borax, sodium phosphate, or sodium acetate. 
It is also soluble in alcohol and w^ood spirit, but is precipitated 
from these solutions by water. It gives reddish-yellow shades. 

Chrysaniline is a yellow powder entirely insoluble in water, 
but soluble in alcohol, and gives a beautiful yellow color. 
Generally the hydrochlorate of chysaniline, found in commerce 
under the name of aurin, is used, it being tolerably soluble in 
water and yielding beautiful golden-yellow colors. Hydro- 
chlorate of chrysaniline forms beautiful red-yellow needles. 

Aniline Red. 

The different red aniline colors known by the names of fuch- 
sine, roseine, azaleine, mauve, solferino, magenta, tyraline, rubine, 
etc., are, no matter how different their mode of production, 
without exception the salts of a base termed by Hofmann 
" rosaniUne.'''' The product is brought into commerce either as 
red powder or, more frequently, as green granular crystals with 
a metallic lustre and sometimes several millimeters in diameter. 
The acetate, known in England and the United States by the 
name of fuchsine, forms especially beautiful crystals. In 
Germany the acetate is termed roseine and the hydrochlorate, 
fuchsine. Aniline red occurs but seldom in the form of a paste 
or in solution. In buying crystallized fuchsine great precaution 
should be exercised, as it is frequently adulterated, especially 
with sugar crystals. Pure fuchsine is sparingly soluble in water 



744 THE MANUFACTURE OF LEATHER, 

of an ordinary temperature, but dissolves readily in hot water 
and very readily in alcoliol, wood spirit, acetic acid, or in a 
solution of tartaric acid. It yields beautiful purple-red solutions 
which are discolored by an addition of alkalies or strong acids. 
The red color of solutions discolored by an addition by alkalies 
is, however, restored by adding acid, and that of those discolored 
by strong acids by an addition of water. 

The nitrate of rosaniline, which is known by the name of 
azaleine, occurs but seldom in commerce, and is distinguished 
from the other varieties of aniline red by the pronounced cherry- 
red color of its solution. 

The article known in commerce Si&diamond 'magenta or fuchsine^ 
is produced in large crystals with a greenish lustre. It has the 
same properties as fuchsine, but has the advantage of being 
non-poisonous, 

Tyraline is another aniline red with nearly the same proper-' 
ties as fuchsine. 

Aniline Brotun. 

Havana hrown is soluble in water, alcohol, and acetic acid. 
It is purified by precipitation from its solution with common 
salt, 

Bismarck hroion is a tarry, black-brown mass not soluble iu 
water but in spirit of wine. The spirituous solution can, after 
mixing with water, be directly used for coloring brown. 

Similar coloring matters known as aniline brown consist fre- 
quently only of by-products obtained by overheating the com- 
position in preparing fuchsine. A special coloring matter 
discovered by Jacobsen, forms a black pulverulent mass insolu- 
ble in water, but soluble in spirit of wine, and gives quite a 
beautiful brown. 

Aniline Black. 

Aniline black is not an actual coloring matter, and does not 
occur as such in commerce, but is best produced directly upon 
the materials to be colored by the action of oxidizing agents 
upon the fabric prepared with an aniline salt (best aniline ace- 



DYEING LEATHER. 7-i5 

tate). The resulting color, which is actually a very dark aniline 
green, is by reason of the insolubility of the product of oxida- 
tion formed upon the fibre itself very fast, and resists more than 
any other black color the action of the most energetic acids and 
bases. To prepare this color numerous receipts have been 
given. Taking the nature of leather into consideration, which 
does not allow of the use of every oxidizing agent, the only one 
of the older receipts available for our purpose is Cordillot's, who 
uses ammonium ferrocyanide as an oxidizing agent. But the 
more recent process discovered by Persoz, Jr., might be still 
more available for leather. The best mode of applying Persoz's 
process to leather is to treat it, after moistening, with a solution 
of 75 grains of potassium bichromate, 45 grains of blue vitriol, 
and 30 grains of sulphuric acid in 2|- pints of water. After 
thorough saturation wash the skins, and after passing them while 
still moist through a dilute solution of oxalate of aniline and 
rinsing them in a bath of tartaric acid, wash them again. They 
will acquire a beautiful black color immediately after passing 
through the aniline bath. Coloring by aniline black might also 
be readily produced by applying, after soaking the skins in a 
solution of sugar of lead, a coat of solution of potassium bichro- 
mate in water and, after washing the painted side which has 
now a yellow appearance, applying to it a coat of solution of 
oxalate of aniline in water to which some sulphuric acid has 
been added. By this process the black color appears also quite 
quickly and remains unchanged by the rinsing in water to 
which the skins must be finally submitted. 

A product recently introduced in commerce under the name 
of " Lucas aniline Mach,^^ offers no special advantages, as the 
semi-liquid black paste consists mainly of hydrochlorate of 
aniline and acetate of copper, and can be readily produced by 
anybody. 

Aniline black is without doubt a very valuable coloring matter, 
and its introduction for coloring leather would be very desir- 
able, a fact of which every tanner would be convinced if he 
would take the trouble of testing its availability by experi- 
ments. 

In connecti,on with aniline black we would mention the aniline 



746 THE MANUFACTURE OF LEATHER. 

gray as one of the more important aniline colors. This coloring 
matter sometimes called murein, in manj respects approaches 
aniline violet, is soluble in boiling water, and yields a pretty 
gray. Another gray produced by the action of aldehyde upon 
aniline violet in the presence of sulphuric acid is, on account of 
its present high price, not adapted for general use. 

Besides the aniline colors which, with the exception of the 
actual rosaniline colors which are not fast, are now doubtless 
permanently introduced into the workshop of the dyer, partly on 
account of their ready application, and partly by reason of their 
brilliancy and freshness of color', there are other colors derived 
from coal tar which are equally valued. To this series belong 
first such as being direct products of the creasote in coal tar, 
are known as 2^henol colors. The most important are the phenol 
red or coralline, or peonine, ■phenol blue or azuline, and phenol 
brown. 

Coralline, 

a magnificent red coloring matter which several years before 
the analysis of Kolb6 and Schmidt, was discovered by Persoz, 
and manufactured on a large scale in a Lyons factory, is a red 
powder scarcel}^ soluble in water but readily in alcohol, yielding 
a scarlet solution. It is also soluble in alkalies, but the solutions 
change readily. It is not changed by acids. Coralline gives to 
alumed leather a beautiful orange-yellow color. To color with 
it dissolve it in alcohol and after adding some caustic soda mix 
the alkaline solution with water acidulated with sufficient acid 
to neutralize the soda. Unfortunately the fiery color which 
coralline yields does not stand exposure to light. Another 
variety of coralline {coralline yellow) differs from coralline red 
by giving a color with an orange tinge. The orange color ob- 
tained with it is very brilliant but will not stand exposure to 
the light. 

Azuline. 

This blue coloring matter, with a shade resembling ultra- 
marine, is a coarse-grained powder with a slight copper lustre, 
and insoluble in water but soluble in alcohol. By heating it 



DYEING- LEATHEE, 747 

with concentrated sulphuric acid for some time, it is, however, 
changed into a product of a like color soluble in water resem- 
bling in this respect aniline blue, which it is greatly like in 
appearance. Azuline may, like coralline, be dissolved in alcohol, 
and after diluting with water containing tartaric acid, be used 
for coloring leather. 

Phenol Broivn. 

The discovery of this beautiful and fast coloring matter was 
made by Roth. It is found in commerce as a delicate brown pow- 
der sparingly soluble in water but readily so in alcohol, acetic 
acid, and alkalies, especially with an addition of some tartaric 
acid. Phenol brown is readily absorbed by leather, and imparts 
to it an agreeable brown color. By adding oxidizing substances, 
such as potassium chromate, to the solution of coloring matter, 
different shades from dark wood-brown to light brown are 
obtained. * 

Another series of colors belonging to this class are the so- 
called naphthalene colors. They are derived from a constituent 
of coal tar, naphthalene, a white crystalline body belonging to 
the hydrocarbons. Although many beautiful and valuable 
colors have been derived from naphthalene they have thus far 
not been so generally introduced as the aniline colors. 

We shall, therefore, only mention the following as samples of 
this series: najyhthylamine violet, naphthylamine red, naphthyl 
hiue resembling alizarine, naphtharazine, and several yellow 
coloring matters, among which that prepared by Martins, 
deserves special consideration. 

This magnificent yellow, known chemically as dinitro-naphtha- 
lene, forms small crystals of a brilliant yellow color and is 
scarcely soluble in water, but dissolves in alcohol and alkalies. 
It is also partly soluble in boiling water. It is not only one of 
the fastest colors, but furnishes also the finest shades, and is 
easily applied, as it is readily absorbed by the fibres. All the 
shades from the lightest lemon color to the darkest golden 
yellow can be produced with it without anything further being- 
necessary than a corresponding concentration of the bath. 

The above-mentioned colors are by no means all that have 



748 THE MANUFACTURE OF LEATHER, 

been brought to our knowledge by recent researches, and we 
could fill page after page in enumerating them, but as many of 
those not mentioned have not been generally introduced into 
practice, and are not regular articles of commerce, we omit them 
here. 

Note. — For portions of the matter contained in the foregoing sections of this 
chapter the author desires to acknowledge his indebtedness to Gintl's Weiss- 
gerberei und Beller's Glacelederfdrheri. 

Section VII. Dyeing Sumach-tanned Skivers with 
Aniline Colors.^ 

We present herewith twelve samples of sumach-tanned skivers 
dyed with a few of the products of the Badische-aniline and 
Soda Fabrik at Ludwigshafen, Bavaria, and sold by W. Pick- 
hardt & Kuttroff", New York, Boston, and Philadelphia. The 
skins shown in the sample* are bleached by acetate of lead and 
sulphuric acid. The Nos. of the patterns correspond with those 
of the first twelve following receipts. For each color, the 
receipt for which is here given, the dye-bath is calculated for 
one dozen skivers, viz., 20 gallons of water. 

•*, 

ISTo. I. Methylene Blue (9, Patented. 

Mordant. — Dissolve 8 ozs. white tartar in 6 gallons of water. 

Enter skivers ; turn 6 times ; lift on the horse. 

Now take : " 

-, , , 1 T x^i r\ • ^ \ W. Pickhardt & Kuttroflf. New 

li oz. methylene blue O, pat. \ ^ ^, .' 

( York, Boston, and Philada. 

Boil in 2 quarts of water. When boiling, add 30 grains com- 
mon salt. 

Prepare dye-bath at 110° F, Add one-half of the prepared 
' blue. Enter skivers ; give 6 turns ; lift, and add balance of pre- 
pared blue. Ke -enter skivers, turn to shade, lift and rinse in 
plenty of water. Stretch on frames and dry. 

1 The author desires to acknowledge his indebtedness to the Textile Colorist, 
published at 50(5 Arch Street, Philadelphia, for the receipts comprised in this 
section. 



II 



III 




IV 




VII 






VIII 





VI 




IX 





XI 




XII 




Page 748. 



DYEING LEATHER. 749 

No. II. Azohenzole Fast Crimson RR^ Patented. 

Mordant. — Dissolve 1 oz. borax in 10 gallons of water. 

Enter skivers ; turn 6 times ; lift on the horse. 
Now take : 
\\ oz. azobenzole fast crimson j W. Pickhardt & Kuttroff, New 

ER. pat. \ York, Boston, and Philada. 

Boil in 2 quarts of water. 

Prepare dye-bath at 110° F., and add one-half of the above 
prepared crimson. Enter skivers ; give 6 turns ; lift, and add 
balance of prepared crimson; re-enter skins; turn to shade; lift 
and rinse. Stretch on frames and dry. 

No. III. Naijhthol Yelloio Z, Patented. 

Mordant. — Dissolve 1 oz, white tartar, 1 oz. tannic acid, in 10 
gallons of water. 

Enter skivers; turn 6 times. Lift on the horse. 

Now take : 

1 ^ i W. Pickhardt & Kuttroff, New 

1 oz. naphthol yellow L, pat. \ ^^ ^ ^ ^ ^_' 

( lork, Boston, and Philada. 

Boil in 2 quarts of water. 

Prepare dye-bath at 110° F. Add one-half of the dissolved 
yellow. Enter skivers; give 6 turns; lift, and add balance of 
dissolved yellow. Re-enter skivers ; turn to shade ; lift and 
rinse. Stretch on frames and dry. 

This is a very fast color. 

No. IV, Leather Broivn. 

Mordant, — Dissolve 3 ozs, white tartar, -1 ozs. alum. 
Enter skivers ; give 6 turns ; lift on the horse. 
Prepare foundation by boiling for 15 minutes 2 gallons of 
water with : 

5 ozs, ext fustic, _ ( ^^ Pickhardt & Kuttroff, New 

1 oz. ext. hy pernio, ■{ -^^ ^ -d ^ j -m -i i 

■^ ^ ' ) 1 ork, Boston, and Philada, 

f oz. ext. logwood, (. 

Make a bath of 10 gallons altogether, at 110° F. Enter 

skivers ; give 6 turns ; lift on the horse. 



1| oz. Victoria green, j 



750 THE MANUFACTURE OF LEATHER. 

Now take : 

n ^ .u \. f W- Pickhardt & Kuttroff, New 

IJ oz. leather brown, < ' 

( York, Boston, and Philada. 

Dissolve in 2 quarts of boiling water. 

Add one-half of the prepared brown to foundation bath. 
Enter skivers ; give 6 turns ; lift, add balance of prepared brown. 
Ee-enter skivers, turn to shade ; lift, rinse, stretch on frames, 
and dry. 

No. V. Victoria Green. 

Mordant. — Dissolve 3 ozs. white tartar, J oz. tartaric acid in 
10 gallons water. 

Enter skivers ; give 6 turns ; lift on the horse. 
Now take 

W. Pickhardt & Kuttroff", New 
York, Boston, and Philada. 

Dissolve in 2 quarts of boiling water; add 1 oz. indigo paste; 
let boil five minutes. 

Prepare dye-bath at 110° F. Add one-half of the prepared 
green. Enter skivers; give 6 turns ; lift, and add balance of 
prepared green. Ee-enter skivers ; turn to shade ; lift, rinse, 
stretch on frames, and dry. 

No. YI. Bark Rose Pink B. 

Mordant. — Dissolve 6 ozs. alum in 10 gallons of water. 

Enter skivers; give 6 turns; lift on the horse. 

Now take : 

o . 1 -n ( W. Pickhardt & Kuttroff', New 

f oz. rose pink B, ^ ^ ' 

( York, Boston, and Philada. 

Dissolve in 2 quarts of boiling water. 

Prepare dye-bath at 110° F. Add one-half of the prepared 
pink. Enter skivers; give 6 turns ; lift, and add balance of pre- 
pared pink. Ee-enter skivers ; turn to shade, lift, rinse, stretch 
on frames, and dry. 

No. VII. Orceine B. 

Mordant. — Dissolve 1 oz. borax in 10 gallons of water. 
Enter skivers; give 6 turns; lift on the horse. 



DYEING LEATHER. 751 

Now take : 

U oz. orceine B, ] ^^- Pi«khardt & Kuttroff, New 

( York, Boston, and Philada. 

Dissolve in 2 quarts of boiling water. 

Prepare dye-bath at 110° F. Add one-balf of the prepared 
orceine. Enter skivers ; give 6 turns ; lift. Pass back through 
mordant-bath ; give 6 turns ; lift, and add balance of prepared 
orceine to dye-bath. Re-enter skivers ; turn to shade ; lift, rinse, 
stretch on frames, and dry. 

No. VIII. Orange BR. 

Mordant. — Dissolve 2 ozs. tannic acid in 10 gallons of water. 

Enter skivers; give 6 turns; lift on the horse. 

Now take : 

R -DT? \ W. Pickhardt & Kuttroff, New 

I oz. orange BK, 1 ^- 

( 1 ork, Boston, and Philada. 

Dissolve in 2 quarts of boiling water. 

Prepare dye-bath at 110° F. Add one-half of the prepared 
orange. Enter skivers ; give 6 turns ; lift, and add balance of 
dyestuflf. Re-enter skivers ; turn to shade ; lift, rinse, stretch 
on frames, and dry. 

No. IX. Bismarck Broivn B. 

Mordant. — Dissolve 3 ozs. tartar, ^ oz. borax, in 10 gallons of 
water. 

Enter skivers ; give 6 turns ; lift on the horse. 

Prepare foundation by boiling for 15 minutes 2 gallons of 
water with : 

4 ozs. ext fustic, ^ j ^^ Pickhardt & Kuttroff, New 

1 oz. ext. hvpernic, ■{ v „i t? ^. i tdi -i i 

^ " ^ / ) York, Boston, and Philada. 

\ oz. ext. logwood, I 

Make a bath of 10 gallons altogether, at 110° F. Enter 

skivers; give 6 turns; lift on the horse. 

Now take : 

-, -D- 1 -D -p S W. Pickhardt & Kuttroff, New 

1 oz. Bismarck Brown K, ^ ' 

( York, Boston, and Philada. 

Dissolve in boiling water. 

Add one-half of the prepared brown to foundation bath. 



752 THE MANUFACTUEE OF LEATHER. 

Enter skivers ; give 6 turns ; lift, and add balance of dyestufif. 
Re-enter skivers ; turn to shade ; lift, rinse, stretch on frames, 
and dry, 

No. X. Fast Brown. 

Mordant. — Dissolve 3 ozs. tartar, 4 ozs. alum, in 10 gallons of 
water. 

Enter skivers ; give 6 turns ; lift on the horse. 

Now take : 

T 1 P , 1 ( W. Pickhardt & Kuttroff, New 

1^ oz. last brown, ^ ^ , ' 

( York, Boston, and Philada. 

Dissolve in 2 quarts of boiling water. 

Prepare dye-bath at 110° F. Add one-half of the prepared 
brown. Enter skivers ; give 10 turns ; lift, and add balance of 
dyestuff. Re-enter skivers ; turn to shade ; lift, rinse, stretch on 
frames, and dry. 

No. XI. SoluMe Blue R. 

Mordant. — Dissolve 1| oz. borax in 10 gallons of water. 
Enter skivers ; give 6 turns ; lift on the horse. 
Now take : 

W. Pickhardt & Kuttroff*. New 



1^ oz. soluble blue R, 

( York, Boston, and Philada. 

Dissolve in 2 quarts of boiling water. 

Prepare dye-bath at 110° F. Add one-half of the prepared 
blue. Enter skivers ; give 6 turns ; lift, and return to mordant- 
bath ; give 6 turns ; lift, and enter dye-bath, to which has been 
added dyestuff ; turn to shade ; lift, rinse, stretch on frames, and 
dry. 

No. XII. Fast Red R, Patented. 

Mordant. — Dissolve 1 oz. borax in 10 gallons of water. 

Enter skivers ; give 6 turns ; lift on the horse. 

Now take : 

-, , f ^ . A Tf + i W. Pickhardt & Kuttroff New 
1^ oz. last 1 eQ XV), pat., ~i 

( York, Boston, and Philada. 

Dissolve in 2 quarts of boiling water. 

Prepare dye-bath at 110° F. Add one-half of the prepared 



DYEING LEATHER. 753 

red. Enter skivers; give 6 turns; lift, and add balance of dje- 
stuff. Re-enter skivers ; turn to shade ; lift, rinse, stretch on 
frames, and dry. 

No. XIII. Brilliant Green. 

Mordant. — Add 1| ozs. sulphuric acid to 10 gallons of water. 

Enter skivers ; give 8 turns ; lift on the horse. 
Now take : 
2 ozs. brilliant green crystals, j Kalle& Co., Biebrich-on-Rhine, 

2 ozs. tartar, I New York and Philadelphia. 

Dissolve in |- a gallon of boiling water. 

Prepare dye-bath of 20 gallons of water at 120° F. Add one- 
half of the prepared brilliant green crystals. Enter skivers ; 
give 6 turns ; lift, and add balance of prepared green. Re-enter 
skivers ; turn to shade ; lift, rinse, stretch on frames, and dry. 

No. XIV. Russia Green. 

Manipulate the same as receipt No. XIII., after dyeing with 
brilliant green crystals. Then prepare a fresh bath of: 

Nitrate of iron, 2° T., i ^- ^^.^^" ^ ^^•' ^^^ ^ork and 

( Philadelphia. 

Enter skivers ; give 6 turns ; lift, rinse well, stretch on frames, 

and dry. 

No. XY. Bose Bengal. 

Mordant. — -Dissolve 6 ozs. alum in 10 gallons water. 

Enter skivers ; give 6 turns ; lift on the horse. 
Now take : 

Heller & Merz, 
New York. 

Dissolve in 2 quarts of boiling water. 

Prepare dye-bath at 110° F. Add one-half of the prepared 
rose Bengal. Enter skivers ; give 6 turns ; lift, and add balance 
of the prepared rose Bengal. Re-enter skivers; turn to shade; 
lift, rinse, stretch on frames, and dry. 

48 



2| ozs. rose Bengal, AT, ■< 



754: THE MANUFACTUEE OF LEATHER. 

No. XVI. Scarlet, No. 2. 

Mordant. — Dissolve 8 ozs. alum in 10 gallons of water. 

Enter skivers ; give 6 turns ; lift on the horse. 
Now take : 

8 ozs. scarlet, No. 2, ( Kalle & Co., Biebrich-on-Rhine, 
1 oz. white tartar, | New York and Philadelphia. 

Dissolve in J a gallon of boiling water. 

Prepare dye-bath at 110° F. Add one-half of the prepared 
scarlet. No. 2. Enter skivers ; give 6 turns ; lift, and add bal- 
ance of prepared scarlet. No. 2. Re-enter skivers ; turn to 
shade ; lift, rinse, stretch on frames, and dry. 

No. XVII. Nanheen Broivn. 

Mordant. — Add IJ oz. tartar and J oz. tartaric acid to 10 
gallons of water. 

Enter skivers; give 8 turns; lift on the horse. 
Now take : 

. 1| oz. nankeen brown, j I. Levinstein, Campbell & Co., 

1 oz. tartar, I New York. 
Dissolve in one-half gallon of boiling water. 

Prepare dye-bath at 120° F. Add one-half of the dissolved 
nankeen brown. Enter skivers ; give 6 turns ; lift, and add 
balance of the dissolved nankeen brown. Re-enter skivers ; 
turn to shade ; lift, rinse, stretch on frames, and dry. 

No. XVIII. Dark Nankeen Brown. 

Manipulate the same as for receipt No. XVII., except in dye- 
bath use : 

3 ozs. nankeen brown, j I. Levinstein, Campbell & Co., 

2 ozs. tartar, ( New York. 

Sectiok VIII. Dyeing Russia and Moeocco Leathers 
WITH Aniline Colors. 

In Jacobsen's Chemisdies Repertoriiim, W. Eitner gives direc- 
tions for the use of aniline colors produced by the Aniline Color 
Manufacturing Co., of Berlin. 



DYEING LEATHER. 755 

The various shades obtained with it are pure and brilliant, 
being not only equal to, but surpassing those obtained with 
decoction of dye-wood. 

Thus far we believe only three shades are manufactured. They 
are known as Eussia leather red G light, Eussia leather red Gr E 
medium, and Eussia leather red E dark. But all three, even 
E, are light as compared with other products, but their tone of 
color is pure and fiery, instead of yellowish. 

The coloring matter which is soluble in water is dissolved in 
boiling water in a clean boiler, the best proportion being 1 part 
by weight of coloring matter to 100 of water. Allow the 
solution to stand quietly for 2 to 3 hours to give any impurities 
a chance to settle. 

For dyeing, mix more or less of the solution, according to the 
size of the skins to be dyed, with warm water. The first pair 
of skins is first brought into a very diluted dye-bath, then into 
a somewhat more concentrated one, and finally into the third, 
which is the most concentrated of all. The second pair of skins 
is brought into the second dye-bath used previously for the first 
pair, and then into the third bath previously used, and finally 
into a fresh dye-bath. 

In this manner each pair of skins receives two dye-baths 
previously used, and one fresh one, the coloring matter being 
by these means thoroughly exhausted and a uniform coloring 
of the skins efiiected. After dyeing, the skins are rinsed by 
drawing them through pure water, and are then stretched, 
and slightly oiled during the latter operation. 

If, in order to produce the odor of Eussia leather, birch tar is 
added to the oil, it is neutralized with soda in case of acid reac- 
tion. 

For the production of yellow and yellowish-brown shades, 
phosphin-orange — composed chiefly of hydrochlorate of chrys- 
aniline and chrj'-sotoluidine — is the most suitable of all tar colors. 
Boil 1 part of coloring matter in 500 parts of water until a per- 
fectly clear solution is obtained which serves directly for the 
dye-bath. The color is very fiery and constant, and loses 
nothing in drying. For many purposes the fiery color of the 
dyed skins is dulled in a bath of potassium bichromate. For 



756 THE MANUFACTURE OF LEATHER. 

dyeing leather golden orange, dissolve 1 part of " Philadelphia 
jellow," manufactured bj the above concern, in 200 parts of 
water, and dilute the solution suflEicientlj for dyeing, or dissolve 
1 part in 300 parts of water, which will give a dye-bath of 
proper concentration. This color, as well as the one previously 
described, does not spot unsound places in the grain, and is 
constant, pure, and fiery. The reddish shade of this group of 
colors is produced in precisely the same manner with Berlin 
blue G, and is not inferior as regards purity, constancj^, and 
brilliancy to the above color. The three colors mentioned are 
specially suitable for brightening dark dye-wood colors by 
placing the leather dyed with Brazil-wood and black in a weak 
batli of one of these colors, the choice depending on the more red- 
dish or yellowish shade desired. Besides the yellowish-brown 
shades, a pureorange, produced with corallin, is also much liked. 
The proportion is 1 part of coloring matter dissolved in 150 parts 
of water. But as corallin upon leather has a tendency to fade, 
the leather must be quickly handled and dried after dyeing. A 
half-dark pale blue, the so-called marine blue, is produced by dis- 
solving 1 part of marine blue in 300 parts of water. Before dyeing 
the leather is not drawn through a bath of very dilute sulphuric 
acid, as is the case in dyeing with other aniline blue colors. 
For pale blue with a pure blue shade, the water blue B B is 
used, and for pale blue with a reddish shade the water blue B. 
Dark blue, which was generally produced in the indigo vat and 
after dyeing with a red coloring matter, is obtained by coloring 
the leather first with blue R or marine blue, and finishing 
dyeing in a second bath prepared by boiling nigrosin in 300 
parts of water. The previous dyeing with blue is necessary 
since nigrosin applied directly to the leather colors badly and 
not uniformly. A beautiful bright green is obtained with 
methyl-green in crystals which is readily soluble in water. Its 
comparatively low price makes its use available for dyeing 
inferior qualities of leather, or at least for brightening leather 
dyed green in the ordinary manner with indigo and fustic. The 
green leather produced in the vat, or as is more frequently the 
case with sulphate of indigo, is washed in cold water in order 
to remove the acid w^hich would alter the methyl-green, and 



DYEING- LEATHER. 757 

receives then a weak bath of methyl-green which will consider- 
ably brighten the originally dull and impure color. For produc- 
ing violet color methyl-violets are the best, as they cover 
excellently, so that the most impure skins can be used for these 
colors. By a proper use of aniline colors, all the inconveniences 
of producing the light shades from yellow to orange so much 
liked at present, with dye-wood colors, are removed, and besides 
much more beautiful tones of color are obtained. The so-called 
Martiii's yellow {hinitronaphthol as calcium or sodium salt) is best 
adapted of all tar colors for the production of pure yellow tones 
of color. It is an orange-red powder which dissolves completely 
in hot water to a pure yellow fluid, and is one of the most con- 
stant and durable colors. Dissolve 1 part of Martin's yellow in 
100 parts of boiling water in an earthen or wooden vessel (all 
contact with metal must be strictly avoided), accelerating the 
solution by stirring with a wooden spatula. After cooling, the 
solution is ready for use. For the production of orange tones 
of the reddest shade, such as are in demand for harness leather, 
a solution of 1 part of aurantia (the ammoniacal salt of hexani- 
trodiphenylanine) in 120 parts of boiling water is used. Phos- 
phin-oranye is also suitable for reddish-orange shades. Dissolve 
1 part of the coloring matter by boiling in 40 parts of water, 
and after allowing the solution to stand quietly one day pour 
off the supernatant clear fluid from the sediment. For use, dilute 
the solution with 50 parts of water. The intermediate shades 
from pure yellow to the reddest orange are produced by mixing 
a solution of Martinis yellow with that of aurantia^ the desired 
shade being determined by experiments. This operation is 
much facilitated by noting down the different proportions and 
adding to the notes a piece of leather dyed with the respective 
mixtures. All the coloring matters mentioned dye directly,, 
requiring no grounding or mordant, and are fast and do not rub 
off". The dyeing is accomplished by spreading the dry leather 
upon a large table and applying the cold color uniformly with a 
long-bristled brush, the latter operation requiring, of course^ 
some skill and care. It is very difficult to color the entire skin 
uniformly and without streaks by one application. It is, there- 
fore, best to dilute the solutions of color given above with an 



758 THE MANUFACTURE OF LEATHER. 

equal part of water and to apply two coats, the second being 
given after the first is dry. Two coats will be suflicient in all 
cases. Harness leather receives generally a more or less intense 
lustre, this being accomplished by rubbing with flannel, or by 
glazing with or without the assistance of wax, cerine, or stearine. 
To give leather straps at the same time color and lustre, a 
single application of orange fat color prepared at the above 
factory is sufficient, 1 part (for very sad color 2 parts) of coloring 
matter is dissolved in 100 parts of boiling water to which 1 part 
of soda has been previously added. Apply the lukewarm solu- 
tion, which gelatinizes on cooling, to the leather with a brush 
or sponge. By rubbing the dry leather gently with flannel, the 
desired lustre is produced. 



CHAPTEE XLIY. 

COMPOUNDS FOR COLORING AND POLISHING LEATHER. 

A Black consisting of an Ainmoniacal Solution of Shellac^ and the 
Aniline Color hnoivn as ^^ Pourrier''s D Blue Aniline.'''' 

This composition, patented by Martyn, is composed of water, 
shellac, spirits of ammonia, and the aniline color, known as 
" Pourrier's D blue aniline," and which, when used in with the 
ammoniacal solution of shellac in proper quantity, produces a 
black. 

To make the composition, take, for 24 ounces of shellac and 
6 gallons of water, 1 pound of spirits of ammonia and 8 ounces 
of the aniline color, and thoroughly mix or stir the whole 
together, the water being heated to about 212° F. Use boiling 
water plentifully with the shellac, the spirits of ammonia, and 
the aniline color in order to combine the ingredients quickly 
and to advantage. 



COMPOUNDS FOK COLOEING AND POLISHING LEATHER. 759 

Protochloride of Iron in Solution as a Basis for Black for Slcins. 

This method, patented bj Brainerd, may be used for coloring 
either partly tanned or fully tanned skins. The iron liquor is 
prepared by dissolving metallic iron in pure hydrochloric acid 
of the shops, at a temperature of about 80° F., until all effer- 
vesence ceases, leaving metallic iron in excess. 

Of this saturated solution of iron take a fluidounce, and dilute 
it with pure soft water, and if the skins are only partly tanned, 
immerse them therein for a period of four or five minutes, keep- 
ing them in constant motion. The dilute iron liquor may be 
applied to the grain of the fully tanned skins with a brush. 

From the iron liquor bath, immediately transfer the skins to 
a bath of clean water, and thoroughly wash, in order to free 
them from any hydrochloric acid that may have been formed by 
the decomposition of the protochloride of iron, by this latter 
element entering into a new combination with the tannin. 

If preferred, the skins may be subjected to the action of a 
bath made slightly alkaline with ammonia, in order to neutral- 
ize any free acid formed. 

The strength of the iron liquor, as above given, will be suffi- 
cient to make a jet black, but a day or two of exposure to the 
air may be necessary to produce the finest tone. A weaker 
iron liquor will give a correspondingly lighter shade of color. 
Skins that have been thoroughly tanned, may, by immersion in 
this iron liquor, be colored through their entire thickness. If 
it is desirable to color only the surface of the skin, it should be 
set out upon the table, while wet, and the iron liquor applied 
with a brush. 

Preparing Raio Hides and imparting Blacky Maroon^ and 
Purple Colors. 

The object of this process, patented by Merrill and Hoitt, is to 
prepare and color raw hides in such a manner that they will be 
permeated by the materials used, and thus rendered more dura- 
ble and neat in appearance for the various purposes to which 
prepared hide is applicable in the arts, such as for tips and 
shields for boots and shoes. 



760 THE MANUFACTURE OF LEATHER. 

The hides are unhaired, fleshed, and rinsed in the usual man- 
ner, and being removed from the rinsing-vat are prepared for 
coloring by being passed through lukewarm logwood liquor, 
made by placing a third of a bushel of logwood, in chips or 
coarse powder, in a bag, in which it is boiled in about twelve 
gallons of water until the strength is extracted. A sufficient 
quantity of the liquor is made for use, as wanted. The hides 
are laid flat, one above the other, in a vat containing sufficient 
logwood liquor to cover them, the temperature of the liquor 
being preferably lukewarm. This liquor may, however, be 
colder than lukewarm, and in such cases the hides must remain 
longer in it. The hides are kept in this liquor for two or three 
days, and are frequently turned until the strength of the logwood 
is extracted and the hides saturated. 

The hides having been treated as described, are then blacked 
in a dyeing liquor made from the solutions here designated for 
convenience of description as Nos. 1 and 2. 

No. 1 is made by boiling together for five or ten minutes four 
ounces each of pulverized nut-galls and blue vitriol in a gallon 
of hot logwood liquor, and afterward adding four quarts of vine- 
gar saturated with iron in any well-known way, or the chemical 
equivalent of the vinegar and iron may be used. 

Solution No. 2 is an iron- set, made by dissolving iron chips 
in aqua fortis or other acids, the iron being added until a satu- 
rated solution is obtained. 

For the purpose of blacking about half a dozen hides, or two 
or three dozen medium-sized skins, place the hides, previously 
soaked in logwood-liquor, in about twenty-four gallons of log- 
wood-liquor such as first described, to which have been added 
two quarts of the solution No. 1 and one pint of No. 2 solution, 
the latter having a tendency to set the color. The hides should 
be allowed to remain in this dye-liquor from one to three days, 
according to their thickness, being frequently turned to secure 
a thorough penetration. 

The exact quantities above given are not arbitrary, as the in- 
gredients vary in strength, and some hides will take color more 
easily than others. The quantities mentioned will generally be 
sufficient to thoroughly black two dozen calf-skins or a half 



COMPOUNDS FOR COLORING AND POLISHING LEATHER. 761 

dozen kips or light cow-hides ; but the heavier hides require to 
remain longer in the compound. 

The dyeing-liquor requires to be replenished as its strength 
is exhausted, by the addition of fresh material, to keep it in 
substantially the proportions described. Maroon and purple 
colors may be made by working in the logwood-liquor and 
finishing by using aqua fortis and tin, with solution of logwood, 
instead of the dyeing-liquor. 

Eawhide, after being subjected to this treatment, in which it 
is only partially tanned, is rendered a deep and permanent color 
throughout its entire surface, and is susceptible of a high polish, 
giving it a finished appearance similar to that of hard black 
rubber. It can be prepared at exceedingly low cost, does not 
become discolored by use, but retains its original neat appear- 
ance until worn out, and is thus of great value in the manufac- 
ture of tips or shields for the toes of boots and shoes, and of 
similar or other articles liable to rough usage. 

Logwood has been described as the base from which the solu- 
tion is obtained. It is selected because it is the cheapest and 
most readily obtained ; but it is evident that more expensive 
materials — as nut-galls and other equivalent dyes from wood or 
vegetables — may be used instead of logwood. 

In the preparation of ISTo. 1 solution we have described that 
the blue vitriol and nut-galls were placed in hot logwood-liquor. 
This is preferable, but instead of logwood-liquor hot water can 
be used, increasing the quantity of nut-galls. 

An Intense Black, etc., jjrepared from Aniline Colors, mixed 
loith Alcohol, etc. 

This compound, patented by Humphrey, is made of aniline- 
red, aniline-blue, and aniline-brown, mixed with alcohol, sul- 
phate of iron, or muriated tincture of iron, water, oil, and 
amber, which, when applied to leather, or other suitable 
material, imparts an intense and durable black color. 

In preparing: Take aniline color one and one-half parts; 
alcohol, one hundred and twelve parts ; sulphate of iron, or 
muriated tincture of iron, sixteen parts; oil, eight parts ; oil of 



762 THE MANUFACTURE OF LEATHER. 

amber and water to suit, usually about two parts of the former 
and eight parts of the latter. 

The aniline colors which the inventor employs, by preference, 
are red aniline, blue aniline, and brown aniline, and he generally 
takes equal quantities of these colors. 

The aniline color is dissolved in the alcohol, and, by the addi- 
tion of oil and sulphate of iron, a compound is obtained which 
will readily combine with the fibres of leather, the oil serving 
to penetrate the material, and to open its fibres, while the sul- 
phate of iron, or muriated tincture of iron, acts as a mordant, 
whereby the color is firmly bound to the fibres. 

In order to reduce the expense of this compound add to it a 
quantity of water, and the inventor also adds amber, for the 
purpose of disguising the smell of the alcohol. 

The color produced on leather is a jet-black ; but, by chang- 
ing the proportions of the aniline colors, different shades may 
be produced. 

Black Staining Gorapound for concealing defects in Leather 
and for applying to Pocket-hooks , composed of Aniline Colors, 
Nap)hthaline^ etc. 

The object of this process, patented by Wolff', is to produce a 
liquid compound which, being applied to the surface of leather, 
will impart a deep, indelible, black color. 

To prepare the compound: Take 0.94 part of blue aniline, 
0.26 part of yellow aniline, 0.48 part of naphthaline, and 0.32 
part of red aniline, which are dissolved in 74 parts of alcohol in 
a suitable vessel by agitation. After being dissolved the liquid 
resulting is passed through a filter. 

It is applied to the leather with a brush, and dries rapidly, 
and, when dry, presents a bronzed appearance, which will be 
converted into a deep black by the application of water with a 
cloth or sponge. 

This staining material can be used in connection with other 
organic substances than leather ; but it is chiefly intended to be 
employed on the latter for the concealment of defective places 
in the blackened surface. 

After application, the leather may be dressed with liquid 



COMPOUNDS FOR COLORING AND POLISHING LEATHER. 763 

blacking or paste, or such materials as are commonlj^ used ; in 
this event dispense with applying water, which is superfluous, 
as the bronzed appearance will be displaced upon the applica- 
tion of such dressing. 

Its effects will be the same on every description of leather ; 
but in classes of leather having a very close grain, such as 
pebble goods and those qualities used in the manufacture of 
pocket-books, etc., two coats of the compound should be applied 
the one upon the other, in order to obtain the desired intense 
black. 

The yellow and blue anilines, by their union, form a green, 
which, by the addition of the naphthaline, is converted into a 
very deep green, so that, by the addition of red, it will produce 
a black. Of itself the mixture of the yellow and blue anilines 
would produce a light green of insufficient depth when mixed 
with the red to produce a deep black. 

Another compound patented by Wolff' consists of the same 
aniline colors as above, but is dissolved only in alcohol and is 
intended to form a base for a black coloring composition for 
leather. 

To prepare this compound : take 0.87 part of blue aniline, 
0.84 of yellow aniline, and 0.29 part of red aniline, and dissolve 
them in 74 parts of alcohol, preferably methylic alcohol, the 
composition, after the complete dissolving of the several 
ingredients, being passed through any appropriate filtering 
medium. 

The result of this combination is a very dense coloring com- 
position possessing great power of penetration. 

The proportions given may be varied to some extent to 
accord with variations in the strength or density of the aniline 
colors employed. 

The compound may be used as a black-varnish ingredient by 
dissolving in it shellac. 

The composition may be used as a base for admixture with 
other materials in order to produce compounds for different 
purposes, such as coloring leather, compound for renovating 
harness, shoe-blackino;, etc. 



764 THE MANUFACTUEE OF LEATHER. 

Compound for iynparting a lustrous Black Gloss to Leather. 

Quinland has patented the following leather dressing com- 
pound for boots and shoes, carriage-tops, harness, trunks, 
satchels, etc., designed to impart to the same a lustrous black 
gloss, as well as to preserve and protect the leather. 

It consists of alcohol, shellac, castor oil, ivory-black, and 
turpentine, in or about the proportions named. 

In preparing : Take one gallon of alcohol, and dissolve in it 
two and a half pounds of orange-shellac. To this add one pint 
of castor oil, one-half pound of ivory-black, and one gill of 
turpentine. 

In adding the ivory-black it is thoroughly incorporated and 
imparts to the liquid a dirty-black color, which, however, when 
applied to the leather surface, becomes, by reason of the evapo- 
ration of the alcohol and turpentine, a rich, lustrous black 
gloss. 

Dyeing Leather.^ containing Tannic or Gallic Acid, Black, hy 
subjecting it to the action of a Yanadic Compound. 

This process, patented by Soerensen, relates to a method of 
dyeing leather black by means that are claimed to be more 
convenient, cleanly, and eft'ectual than when the ordinary 
methods are employed. 

The leather to which this manner of dyeing applies is such as 
has been tanned, and contains tannic acid, or gallic acid, or any 
of those derivations or combinations of or with which such 
analogous acids as turn black when acted on by compounds of 
vernadium. The dyeing can be effected at any time after the 
leather has been tanned. The action of the vanadic compound 
or preparation — which is employed in solution — on the surface 
or body of the leather treated is to turn it black. 

It will be well understood that in order not to in any way in- 
juriously affect the qualitj'- of the leather it will be most advan- 
tageous to employ a neutral vanadic solution, and the inventor 
claims to have successfully used a neutral solution of vanadiate 
of ammonia containing one per cent, of the latter salt. In order 



COMPOUNDS FOR COLORING AND POLISHING LEATHER. 765 

to bring out a full black color the moderate use of heat is bene- 
ficial. 

Blackening leather by vanadium preparations is claimed to 
be especially advantageous in the treatment of manufactured 
articles, such as boots and shoes, as the risk of damaging the 
upper portions of the same is avoided, and in the case of orna- 
mental stitching in saddleryware the leather is rendered black, 
while the stitching retains its proper color. It also allows the 
operation to be performed without soiling the hands. 

Gilding and Ornamentiny Leather for Suspender Ends^ etc. 

The method patented by Walker consists in gilding or bronz- 
ing leather used for suspenders' ends with gold leaf, metal foil, 
or with bronze, either in the form of leaf or in powder. The 
gilt or foil or leaf is applied by means of stamps or dies contain- 
ing any suitable ornamental design, and may be applied by any 
of the means now used, for imparting ornamental designs to 
leather by means of gilding and bronzing. The processes, being 
well understood by the workers in this method of ornamenting 
leather, need not be particularly described. 

If the leather is dyed, it should be with fast colors, so that no 
stain will be imparted to the clothing. When artificial leather 
is used, it can be treated in the same way as real leather. 

Gilding Leather. 

The Papierzeitung gives the following method described for 
gilding leather. It is first moistened with a sponge, then 
stretched and tacked on a board. When dry it receives a coat 
of thick isinglass solution, then one of white of egg that has 
been beaten and allowed to settle. Upon this are laid lightly 
with a brush sheets of silver foil, which are then pressed down 
with a wad of cotton-wool. When this is dry it is painted over 
with yellow leather varnish, which gives it a beautiful golden 
appearance. 

Bronze Dressing for Leather. 

The object of this method, patented by Fennessy, is to pro- 
vide a cheap and brilliant bronze dressing for leather, to be used 



766 THE MANUFACTURE OF LEATHER. 

particularly for bronzing boots and shoes; and consists in a 
preparation composed of aniline red, blue, violet, or purple, or 
a mixture of two or more of these colors, dissolved in a suitable 
acid, and brought to the desired consistency by the addition of 
an acid solution of gelatine or a gum soluble in water. 

To prepare : Take six ounces of aniline red and two ounces 
of aniline blue, violet, or purple, dissolve them in one quart of 
acetic acid, heating the mixture slightly in order to accelerate 
the operation, after which it is allowed to become cool. Then 
dissolve in a separate vessel thirty-two ounces of gelatine in one 
gallon of acetic acid, and add this mixture to that first described, 
after it has become cool, to give the required consistency to 
the compound. The whole is then thoroughly stirred together, 
when it is ready for use. 

Any suitable acid other than acetic acid may be used ; and in 
lieu of gelatine, a gum soluble in water— for instance, gum 
arable, or gum tragacanth — may be employed, if desired. The 
proportions of aniline color or acid above stated may be varied 
somewhat according to the shade of bronze required ; and any 
one of the aniline colors above referred to may be used singly 
instead of a mixture of these colors ; but the inventor prefers 
the mixture first described, as it produces a more desirable shade 
of bronze. The quantity of gelatine or gum used may also be 
varied, according to the consistency required. 

The dressing is applied with a soft brush, and gives a brilliant 
bronze finish to the leather. 

Aniline Bronze Colors of Various Shades applicalle to Leather. 

This method, which is that of Fiorillo, consists, broadly, in 
the admixture of benzoic acid with aniline colors, for the pur- 
pose of producing a bronze paint or color, the shade or tint of 
which may be varied according to the aniline colors used and 
the detailed treatment to which they are subjected during 
the process. 

To compound this bronze proceed as follows: Dissolve ten 
parts of aniline red, or so-called diamond fuchsine or roseine, 
and five parts of aniline purple (known in commerce as " Hof- 
man's violet" or methyl violet) in. one hundred parts of alcohol 



COMPOUNDS FOR COLORING AND POLISHING LEATHER. 767 

of 95° strength, placing the vessel containing the mixture in a 
hot-water or sand bath, to promote the dissolution. As soon as 
the aniline*ha^ been dissolved in the alcohol add five parts ben- 
zoic acid, boil gently, then add thirty-two parts of gum benzoin, 
and continue boiling from five to ten minutes, until the can- 
tharide-green color of the mixture disappears, changing into a 
bright golden bronze color. 

The color thus produced is of a very high lustre, of great 
durability, and will adhere firmly to leather, and, in fact, to 
nearly all substances. It is readily applied with a brush, and 
dries in a few minutes. It will answer equally well on white 
and colored grounds ; and may be used, on account of its 
durability and the facility with which it is applied, upon 
ladies' boots, slippers, shoes, or other articles of leather, to 
which it imparts a bright golden bronze hue. . 

Producing wpon Leather Various Shades of light broivn, and 
darker colors^ hy the combination of Oxalic Acid, Salt of Tin, 
and Potash, with Nut-gall and Sulphate of Iron. 

The process patented by Jager consists in washing the leather 
with the solution of salt of tin and oxalic acid to prepare it for 
receiving the color. Potash, nut-gall, and sulphate of iron are 
the ingredients of the compound for coloring. 

The proportion of ingredients composing the wash for pre- 
paring the leather is one part of oxalic acid to three parts of 
water. With this solution the inventor washes all kinds of 
grain leather. With the solution of one part of salt of tin and 
three parts of water he washes all split leather and leather 
without grain. After the leather is perfectly dry it is ready to 
receive the color. The compound used to give the leather the 
various shades of light broAvn is composed of one part of potash 
and three parts of water. To get the various shades desired 
increase or decrease the strength of the solution. It is applied 
with an ordinary brush. For dark colors use the following 
compound : one part of sulphate of iron, one part of nut-gall, 
and three parts of water. This is also applied to the leather as 
stated. For the purpose of shading the color on the leather a 
solution of oxalic acid is prepared and slightly applied with a 



768 THE MAISrUFACTUEE OF LEATHER. 

sponge till the shades suit the operator. After the paint is well 
dried a mixture of starch and the white of egg is used for coat- 
ing the leather. After the coating has well dried the leather is 
ready to receive the varnish. 

Coloring Leather voitli Aniline upon a Starched Surface and 
produciny an appearance similar to Marhled Paper. 

This process, which is that of Koppitz and Mayer, is carried 
out by mixing the ground color with starch ; as, for instance, if 
logwood is used as a ground color, the inventors boil it in vinegar 
until the color is sufficiently extracted, and after having stained 
the solution there is mixed with it a quantity of starch, generally 
one pound of starch to one quart of the solution, although the 
proportions are to be varied according to circumstances, For 
further coloring the leather the inventors use various aniline 
pigments, each of which is prepared as follows : First dissolve 
the color in alcohol, using for each ounce of the aniline pigment 
about one pint of alcohol. To this add about three quarts of 
vinegar, and next boil the solution for a few minutes, after which 
it is ready for use. 

Next, the preparation of ground color is sprinkled on the 
leather or the latter is covered with the preparation to the 
necessary extent, after which the other color or colors or prepa- 
ration of aniline, as above explained, is to be sprinkled or 
thrown upon the leather to the extent required. The starch of 
the first preparation will cause it to resist the aniline color or 
colors, or second preparation, whereby there will result a soft- 
ening or shading together of the spots of ground and other colors 
at their edges in contact. This softening or blending of the 
masses or spots of colors at their edges with the ground colors 
produces a very 23leasing effect, and although the leather has an 
appearance much like that of marbled paper, used in book-bind- 
ing, no bath is required to produce the effect, as in the process 
of marbling paper. Furthermore, the preparation of the aniline 
color, by the employment of alcohol and vinegar, in manner as 
described, renders the color stable, or not easily oxidizable by 
light, the preparation being peculiarly fitted for coloring leather 



COMPOUNDS FOR COLORING AND POLISHING LEATHER, 769 

with one plain color without first employing a ground color 
prepared with starch, as set forth. 

We would observe that, generally speaking, whenever the 
ground color prepared with starch, as explained, becomes cov- 
ered with the aniline color, the latter becomes readily remov- 
able by water, so that, after a skin may have been sprinkled 
with the ground and aniline dyes or colors, and is afterward 
washed, the aniline colors will remain fast in such portions of 
the skin not covered by the ground or starch color, but will be 
mostly if not entirely removed from the parts on which the 
starch color or ground may have been thrown. By this process 
it is possible to color leather or other substances for use in the 
arts with great economy, and with excellent practical and orna- 
mental results. 

Forming a Solution for Staining Tawed Leather^ consisting in 
, mixing Clay, Water ^ Comm^on Salt, Sulphuric Acid, Brewer's 
Yeast, Ahcrn, Hemlock Extract, and Terra- Jaiponica. 

This process, patented by Eichter, is carried out as follows : 
Prepare a clay mixture by filling a barrel or other vessel half- 
full of clay (preferably clay suitable for making bricks). Then 
add water sufficient to thoroughly reduce the clay, destroying 
its adhesive qualities and forming a mixture of thick or semi- 
liquid condition. Then mix therewith the following ingredients, 
in substantially the following proportions, viz : To every 
thirty-two gallons of the clay and water mixture add four quarts 
of common salt, one pint of sulphuric acid, and presently add 
one quart of brewer's yeast, and thoroughly incorporate them. 
An effervescence Avill ensue and continue for about twenty-four 
hours, and when it ceases the liquid compound will begin to 
precipitate. Then remove the impurities deposited and leave 
the supernatant water, and fill the barrel or other vessel with 
water and dissolve therein six ounces of alum to every thirty- 
two gallons of liquid. Then add to this mixture one pound of 
hemlock extract and one pound of terra-japonica thoroughly 
dissolved in hot water. Apply to the hides, after being tawed 
and dressed, by pouring the mixture over them when in a close 
49 



770 THE MANUFACTUEE OF LEATHEE. 



vessel, so as to cover them, and keep about tliirty-four hours in 
solution. 

Preparing^ coloring^ and poll sliing Light Skins for Car Seats^ 
Trunk Covers^ etc. 

This process, patented by Djar, relates to the preparation of 
leather for the purpose of imparting a finished or ornamented 
surface to the same, having particular reference to converting 
cheap or light skins into material for car seats and linings, boot 
and shoe linings, trunk covers, etc., where light stock may be 
used to advantage, if it has a finished and uniform surface. 

In accomplishing this object the surface of the skin to be 
prepared is first filled with a composition (using a compound 
which can be polished by friction), and the dead or lustreless 
surface of the leather left by application of the composition is 
next printed (by any one of the ordinary printing processes) 
with any suitable design or figures, and in any desired colors. 
The surface is then solidified and polished by working a tool 
over the skin, laid upon a bed, as in ordinary levelling, solidifying, 
or polishing machines. The skin to be prepared is preferably in a 
dry condition when treated, and the composition the inventor 
prefers to use is made up of a mucilage or pulp obtained by 
soaking flaxseed in water, and straining oft" the pulp, and dis- 
solving in the pulp, freed from the seed, white soap, adding also 
a little linseed or other oil. This composition is thoroughly 
worked into the surface of the leather, and the leather subse- 
quently dried. Then the pattern or design is laid or printed on 
the prepared surface, after which the leather is subjected to the 
action of the- polishing tool, the mucilaginous and saponaceous 
surface so combining with the imprinted colors that a uniformly 
polished and hardened surface is imparted to the whole skin, 
the tool gliding over the printed characters without moving or 
spreading them. Deer, neat, goat, calf, and sheep-skins maj'- 
all be prepared in this manner, and upon either the grain or 
flesh side, as circumstances may make desirable. 



COMPOUNDS FOR COLORING AND POLISHING LEATHER. 771 

Composition of Olycerine^ Resinous and other Substances afford- 
ing a Base for inipartinx] a High Polish to Leather. 

The composition patented by Farnbam, is intended for appli- 
cation to leather- work, for the purpose of rendering the leather 
impervious to water, and at the same time affording a base which 
is susceptible of receiving a high polish, preserving, also, the 
flexibility of the leather. 

The employment of resinous substances as a coating for leather 
has been objectionable, because such resinous substances, on 
becoming dry, would crack, and cause the leather to break. It 
is claimed, that by mixing glycerine with a resinous compound, 
an article will be produced meeting all the requirements, viz., 
the exclusion of water, the preservation of the softness of the 
leather, and the susceptibility of the compound to receive a high 
polish. 

To make this preparation take of alcohol (ninety-four per 
cent.) one gallon; Venice terebinthina, one pound; gum-shellac, 
one pound; glj'cerine, one pound; myrtle-wax, one-fourth pound, 
and of fine lamp or ivory-black, enough to give the requisite 
color and consistency. 

Digest the gum in the alcohol until thoroughly dissolved. A 
portion of the glycerine is used in grinding the myrtle-wax, and 
a portion in grinding the blacking, so as to make it perfectly 
soluble in the alcohol. The ingredients, after being mixed, 
must be stirred until a perfect union is effected. The composi- 
tion is to be applied to the leather with a brush or sponge, in 
the usual manner. 

Castor oil ma}^ be used with the glycerine resin, for carriage- 
tops and other work where a brilliant polish is not required. 

Composition for Polishing, Water-proofing, and' Coloring Leather. 

In making this composition, which is the invention of Martyn, 
proceed as follows : To one imperial gallon of water add three 
ounces of nut-galls, and heat the water and' maintain it at a sim- 
mering temperature for about half an hour, so as. to thoroughly 
extract the tannin from the galls.. Next remove the liquid 
from the galls, and raise it to a boijirjg. heat,, and while at this 



772 THE MAKtlFACTtrJlE OF LEATHER. 

boiling terapefattire introduce two ounces of strong spirits of 
ammonia, borax, or other suitable alkali, and one and one-half 
pounds of gum-shellac, and stir the whole until thorough solu- 
tion of the shellac takes place, Next add to the solution one 
drachm of aniline color in crystal, using generally " aniline- 
blue," or violet, or both, or an aniline-black, for instance. 
Next add to the solution three ounces of vegetable, ivory, or 
lampblack. After stirring until the latter addition is well 
incorporated, the composition will be complete and ready for 
use. 

It is to be applied to the leather, boot, shoe, or other article 
by means of a brush or sponge, and when dry will be found to 
impart to it a brilliant enamel surface, one impervious to water. 
The proportions of the ingredients may be varied somewhat, 
more or less, without materially changing the character of the 
process. , 

The vegetable, ivory, or lampblack will, by the gum, be held 
in suspension in the liquid, but the compound should be 
thoroughly stirred every time before using, 

Polish for Leather used for Bags, Satchels, etc. 

This polish, patented by Bddlemon and Walker, is in the 
nature of a blacking, and to prepare it mix the following ingre- 
dients in the proportions stated, viz: 1 quart alcohol, 4J ounces 
gum shellac, 3 ounces English rosin, 1 ounce oil of sassafras, 1 
ounce castor oil, 1 ounce lampblack, and f of an ounce beeswax. 
These ingredients are placed in a tin vessel over a slow fire, 
stirring frequently until the shellac, rosin, and beeswax are 
dissolved, and the whole mixed thoroughly, which will require 
from twenty to thirty minutes. It is then removed from the 
fire, and, after cooling oS", is ready for use. 

This polish may be used for bags, satchels, harness, boots, 
shoes,, and all other leather goods, as it will not rub off', but 
gives it a fine and lasting gloss, besides softening the leather 
and rendering it water-proof by filling the pores. It may be 
applied with a brush or soft rag (a piece of flannel is the best), 
or a sponge may be used, if desired. Several of the ingredients 
named have been used before separately or in different combi- 



COMPOUNDS FOR COLOKIISrG- AND POLISHING LEATHER. 773 

nations in the manufacture of leather-polish, notably the combi- 
nations of alcohol, gum-shellac, rosin, and lampblack, or other 
coloring matter, and these combinations are not claimed in this 
patent; but only those ingredients in the proportions above set 
out. 

Coloring partially tanned Hides and Skins by the employment of 
a Bath of Tin, Acid and Water, and Turmeric. 

In carrying out this process, which is that of Woodbury, sub- 
mit the skin or hide, after its outer and inner layers have been, 
tanned sufficiently, to the action of a bath composed of a solution 
of nitrate or muriate of tin, or nitrate or muriate of tin and 
a coloring matter, such as turmeric, for instance. In this bath 
allow the skin or hide to remain from twelve to twenty-four 
hours or thereabout, when it will be found, after removing the 
skin from the bath and washing it, that the tannin in the outer 
layers, or much of it, will have been thoroughly driven or forced 
into the inner layer, and a uniform or practically uniform tan- 
ning of the whole skin or hide will have taken place ; also, 
that the tannin or coloring matter will have penetrated the 
entire skin so as to color or modify the color of it, as may be 
desirable. In preparing the bath of nitrate or muriate of tin 
take for each gallon of nitric or muriatic acid about one pound 
of the metal tin. The acid is to be poured upon the tin, or the 
latter is to be immersed in the acid, and the two are to be al- 
lowed to stand until the tin may have been dissolved or destroyed 
by the acid, after which there may be added to the solution the 
necessary amount of water, say about 140 gallons, and the tur- 
meric or coloring matter. 

Compound for changing the coloi; of Leather, especially the color 
of the soles of Boots and Shoes. 

This process, patented by May, relates to a compound to be 
applied to leather in the manufacture of boots and shoes, and 
for leather used for other purposes, for changing the color of 
the leather, designed more especially for changing the color of 
the soles or bottoms of boots and shoes, but not confined thereto; 
and it consists in the following compound : Take 2 gallons rye- 



774 



THE MANUFACTURE OF LEATHER, 



flour paste; 2 gallons tragacantli paste; 1 pound American 
isinglass; IJ pound oxalic acid; ^ pound gum gamboge; 3 
pounds pipe-clay, united with water sufficient to make 10 gal- 
lons of the compound of the proper consistency for use. 

The mode of preparation is substantially as follows : While 
the rye paste (made in the usual way) is hot, add the isinglass 
and stir until all is dissolved ; then add the tragacantli paste ; 
then let the mass cool, and, when cold, add the oxalic acid, gum 
gamboge, and pipe-clay and water. Let the composition stand 
for the space of a week or so before using. 

This composition fills the pores and makes the leather bright 
and hard. By the use of a revolving brush, or of friction applied 
otherwise after the application of the composition, the complex- 
ion or color of the leather may be changed, as desired. The 
bottom of a boot or shoe or other leather may be made of a 
very light color, or of a dark red or other complexion or shade. 
The color, it is claimed, will not fade, and the application of the 
compound, it is also claimed, improves the wear or durability of 
the leather. 

Compound for Whitening Leather. 

Tinnerholm's process for whitening leather is as follows: 
He takes — 



Acid, tartar., crys. 


2 ounces 


Acid, muriatic, 


crys. 


2 " 


Cream tartar 




2 " 


Sulphur 


. 


. 2 " 


Water 


. 


. 20 gallons 



The above ingredients are mixed and placed in the vats with 
the hides, and in it they remain for two hours. 






COMPOUNDS FOR COLORING AND POLISHING LEATHER. 775 

List of all Patents for Compounds for Coloring and Polishing Leather^ 
issued by the Government of the United States of America, from 1790 
to 1883 inclusive. 



No. 




Date 




Inventor. 


Residence. 


5,327 


Oct. 


9, 


1847. 


W. Mc Adams, 


Albany, N. Y. 


33,331 


Sept 


24, 


1861. 


J. Braiuerd, 


Cleveland, Ohio. 


46,804 


Mar. 


14, 


1865. 


X. Karcheski, 


Bellville, N. J. 


62,120 


Feb. 


19, 


1867. 


S. Dyar, 


Charlestown, Mass. 


77,021 


Apr. 


21, 


1868. 


T. M. Farnham, 


Tully, N. Y. 


118,089 


Aug 


15, 


1871. 


D. Woodbury, 


Feabody, Mass. 


121,375 


Nov. 


13, 


1871. 


G. Jager, 


Indianapolis, Ind. 


124,965 


Mar. 


26, 


1872. 


T. C. May, 


Cochituate, Mass. 


130,958 


Aug. 


27, 


1872. 


G. W. Walker, 


Lowell, Mass. 


142,797 


Mar. 


29, 


1873. 


J. Koppitz and 
F. B. Mayer, 


Boston, Mass. 
Canibridgeport, Mass. 


147,337 


Feb. 


10, 


1874. 


H. Martyn, 


Martha's Vineyard, Mass 


158,608 


Jan. 


12, 


1875. 


C. J. Tinnerholm, 


Keokuk, la. 


164,678 


June 


22, 


1875. 


E. H. Fennessy, 


Newton, Mass. 


165,129 


June 


29, 


1875. 


H. Smith, 


Newark, N. J. 


167,183 


Aug. 


31, 


1875. 


H. Martyn, 


Boston, Mass. 


170,100 


Nov. 


16, 


1875. 


H. W. Merrill and 
J. W. Hoitt, 


Lynn, Mass. 


171,787 


Jan. 


4, 


1876. 


Otto Fiorillo, 


Baltimore, Md. 


179,560 


July 


4, 


1876. 


A. S. Humphrey, 


Poughkeepsie, N. Y. 


190,660 


May 


8, 


1877. 


Geo. S. Wolff, 


Pliiladelphia, Pa. 


194,754 


Aug. 


28, 


1877. 


Geo. S. Wolff, 


Philadelphia, Pa. 


203,498 


May 


7, 


1878. 


N. Quinlaii and 
J. H. Quinlan, 


Glens Falls, N. Y. 


225,772 


Mar. 


23, 


1880. 


M. B. Tice, 


Newark, N. J. 


243,000 


June 


14, 


1881. 


N. G. Sorensen, 


Stockholm, Sweden. 


265,041 


Sept, 


26, 


1882. 


J. F. Eddlemon, and 
W. L. Walker, 


Witcherville, Ark. 



INDEX. 



ABIES CANADENSIS, 118 
Abraham and Lot, rich in cattle, 
silver and gold, 34 
Acacia bambula, 118 

catechu, 114 
Acetate of potash, 105 
Acetates, 715-717 
Acetic acid, 708 

use of in separating coriin, 
97, 99 
Acid, acetic, 97, 99, 101, 708 

iesculotannic, 120 

arsenic, 105 

arsenious, 52 

carbolic, 48, 50, 53, 344 

carbonic, 105 

cashew-tannic, 101 

chromic, 53, 61, 62, 107, 134 

citric, 709 

colfee-tannic, 101 

digallic, 108 

ellagic, 107 

formic, 120 

gallic,.^ 08 

gallotnnnic, 101, 103, 108, 109 

hydrochloric, 82, 83, 97, 99, 105. 
107, 707, 708 

iodic, 106 

lactic, 112 

li(pors, depilating with, 265 

metagallic, 105 

mineral, the principtd ones em- 
ployed in dyeing leather, 706 

morintannic, 101 

nitric, 83, 86, 707 

oxalic, 107, 708 

phosphoric, 105 

phyllocitannic, 120 

physiological and pathological 
tannic, 102 

picric, 138 

propionic, 112 

protocatechuic, 120 

pyrogallic, 105, 113 

pyroligneous, 52, 708 



Acid — 

quercotannic, 110 

quinotannic, 101 

rufigallic, 109 

rufitannic, 110 

suberic, 107 

sulphuric, 86, 105, 706 

tannic, 97, 99, 100, 113, 114, 116 

tannomelanic, 1 09 

tannopinic, 109 

tannoxylic, 110 

tartaric, 709 
Acids, 705, 706 

in sour liquor, 360 

mineral and organic, 706 
depilating with, 265 

organic, which are of interest to 
the dyer, 708 

the action of, on tannin, 106, 107 

the swelling influence of, on skin, 
100 
Adamson's bating process, 349 
Adipose tissue, lobules of, 95 
Adler's compound for depilating and 

swelling hides, 273, 274 
^sculetin hydrate, 120 
^^ivsculotannic acid, 120 
tEscuIus hippocastanum, 120 
Africa, goat-skins of, 42 
African kino, 114 
Agamemnon, the boots of, 57 
Agitators, patents for, 358, 359 
Aikin, 58 
Aikins's method of working lamb-skins 

into glove leather, 664-669 
Air bath for the determination of water 

in leather, 82 
Alaska, seal-skins of, 43, 44 
Alazarine red, 735 
Albumen, use of in bating, 346 
Alcohol, extracting resinous substances 
from leather with, 127 

its employment in determining 
fats and resin in leather, 82 

use of, for dissolving tannin, 103 



778 



INDEX. 



Alcohol — 

use of, for exhausting gall-nuts, 104 
Aldehyde green, 742 
Alder 'bark. 121 
Aleppo fir, bark of, 121 
Algarohia f/landuloxa, 122 
Alkalies, action of the, on tannin, 107 
Alkaline carbonate solution, 137 
chromates, neutral, 134 
mordant, 726 
sulphates, 131 
Allen and Wai-ren's hanging sprinkler, 
208 
sprinkler leach, 203, 204 
system of leaching with little 
or no heat, 223 
Alligator leather, 582-585 
uses of, 582 
skin, japanned leather in imitation 
of, 594, 595 
of the, 36 
skins, bate for, 584 

packing, shipping, and trade 

in, 5"82, 583 
tool for softening, 584 
treatment of, 583-585 
whence obtained, and their 
uses, 44 
Almond oil for tawing, 65G 
Aloes, 52 
Alum, 712, 713 

absorbed by a complete saturation 

of the skin tissue, 132 
according to Knapp and Reimer 
is split in being absorbed by the 
skin tissue, 132 
ammonia, 131 
chromium, 132 
concenti-ated, 130-132 
cubic, 131 
for bating, 386 
formation of, 131 
formula of, 130 
for tanning, 628 
for tawing, 654 
iron, 132 

iron and chrome in tanning, 629 
leather, 69 
manganese, 132 
potash, 131 
Kunge's test of, 713 
tanning properties of, what prin- 
cipally due to, 132 
Alumed leathers, defects of, 673-67-9 
leather. Main's process of finish- 
ing, 667, 668 



Alumina, 53 

Aluminium acetate, 132, 133, 715, 716, 
chloride, its use for increasing the 

weight of leather, 86 
salts, ammonium hydrate as a 
reagent for, 86 
in tanning, 633 
sulphate, 130-132 

to test, 131 
tanning, 641 
American hemlock extract, 119 
leather, high rank of, 78 
patent system, 54 
potash, 51 
sumach, 116 
Ammonia, 107 

alum, 131, 713 

and blood for bating, 285 

carbonate of, for accomplishing the 

purposes of the bate, 336 
muriate of, for bating, 336 
Ammoniacal solution of zinc acetate, 
use of in determining tannic acid, 143 
Ammonium hydrate as a reagent for 
aluminium salts, 86 
its use in determining the 
percentage of lime in 
leather, 83 
nitrate, its use in determining the 
percentage of ash in leather, 82 
oxalate, its employment in deter- 
mining lime in leather, 82 
Analyses of vegetable tanning mate- 
rials by various processes, 138-164 
Analysis, qualitative, of water, 169 
Anderson's depilatory of cRarcoal, 277 
Aniline, 746, 747 
black, 7 44, 746 
blue, 742 

ordinary, 742 
bronze colors, application of, to 

leather, 766, 767 
brown, 744 

colors and alcohol, compound of, 
for imparting an intense black 
to leather, 761, 762 
colors, dyeing Russia and Moroc- 
co leather with, 754, 755 
dyeing sumach-tanned ski- 
vers with, 748-754 
dyeing with and the methods 
of their preparation, 740- 
748 
especially suitable for leather, 

740 
for dyeing parchment, 741 



INDEX. 



779 



Aniline colors — 

for oil or chamois leather, 

741 
high perfe(!tioii of this indus- 
try, 704, 705 
naphthaline, etc., for making 
a black staining compound, 
762, 763 
on Morocco, advantages in 

using, 757 
upon a starch surface on 
leather, producing an ap- 
pearance similar to marble 
paper, 768, 769 
gray, 745 
green, 742, 743 
red, 743, 744 
violet, 741, 742 
yellow, 743 

ordinary, 743 
Animal charcoal, extraction of, with 
hydrochloric acid, 156 
kingdom, 36 
skin, 93-100 

construction of, 93 

Anthon on the quantities of various 

tannins required for the conversion 

of one pound of skin into leather, 

125, 126 

Antiseptic substances for preserving 

hides, 50 
Apparatus for stretching leather, 

patents for, 596 
Apparatuses for blacking leather, 
patents for, 449 
for tanning goat and sheep-skins, 
536-545 " 
Applying the dye, 730 
Areometer, the, 139, 14 7 
Arsenic acid, 105 
Arsenious acid, 52 
Art, the improvement of an, 56 
Artificial leather, of what made and 
its uses, 72, 73 
Russia leather, 581, 582 
sheep-skins for linings, 561, 563 
sole leather, 489-491 

by Pollock's process, the 

chemical reaction 

"which takes place in, 

491 

impervious to water, 

489, 490 
large quantities produced 
in Massachusetts from 
leather scraps, 489 



Artificial — 

tannin of resin, camphor, and sul- 
phuric ac"id, 137 
tannins, chemical nature of them 
not thoroughly investigated,. 
137, 138 
Artificially prepared tanning sub- 
stances, 136-138 
Ash, percentage of in leather, deter- 
mination of, 82, 83 
Ashton's process for tanning with fer- 
ric salts, 626, 627 
Asia Minor, goat-skins of, 43 

trade of in lamb-skins, 42 
Aspidosperma quebracho, 122 
Aspidospermin, 122 
Astringent principle of hemlock and 

oak bark alike, 481, 482 
Australia, kangaroo leather in, 583 
Avens root, 122 
Azaleine, 743 

Azobenzole, fast crimson E, R for 
skivers, 749 



BACTERIUM ANTHRAX, poi- 
soning by, 48 
Badische aniline and soda fabrik ani- 
line colors, 748 
Baker's improved glazing machine, 
462, 463 
improvement on Coogan's board- 
ing and graining machine, 438, 
439 
pony glazing machine, 463, 464 
vat with feeding pipe for Morocco 
tanning, 527, 528 
Ballamy, 59 

Bahamokarpon hrevifolium, 122 
Bamboo, silica in the epidermis of, 

175 
Bantsia serrata, 121 
Banks's discovery of the tanning pro 

perty of terra japonica, 58, 59 
Barberry yellow, 734 
Barber's bark mill, 188-190 
Barium, 134 

chloride, its use for increasing the 
weight of leather, 86 
of, 61 

of, how determined in the 
percentage of ash, 82 
sulphide of, for softening, plump- 
ing, and depilating hides and 
skins, 282, 283 



780 



INDEX. 



Bark, 174-183 

bought in Massachusetts by the 
cord, 494 

chestnut oak, 119 

contrivance for cutting prepara- 
tory to peeling the same, 178- 

isl 

conveyer, 200-202 

cutch and gambir, exports and 

imports of, 79 
epidermis of, 174 
extracts, 494 

of, purifying, 227-231 
removing resinous gums and 
floating particles from, 227 
use of in the United States, 
598 
grinding and leaching of, import- 
ance of in tanning, 184 
mill, Barber's, 188-190 

one of the prime require- 
ments of a, 184 
safety, coupling of, to prevent 
breakage should a foreign 
substance get into it, 186- 
188 
Troy or Starbuck, arrange- 
ment of, 185 
Weston's horizontal cylinder, 

185 
with rotary cutters, 190-195 
mills, different varieties of Ameri- 
can, 185 
patents for, 195-197 
oak, chemical examination of, 
159-163 
to obtain a correct sample of 
for analysis, 160 
peeling, and the most convenient 

time for it, 176, 177 
quantities of oak and hemlock, 
consumed in the United States, 
75 
rock oak, 1 19 
rossing, 181, 182 

machines, patents for, 182 
the, from which tannin is obtained, 

181 
the more unevenly ground the 
more unevenly it is leached, 
184 
the nature of, 174-176 
the outer coating of, loses its tan- 
ning properties, 181 
used for grain, split, and buff 
leathers, 511 



Barking, influence of seasons and 
place at the time of, on the 
richness in tannin, 177 
tools used in, 177, 178 
Barkometer, the, 221, 226 
Barks used in tanning, 118-121 
Barley dressing, 300 
raising by, 300 
Barrentrapp-Will method of analysis, 

84 
Barron's process for softening dry 

hides, skins, and peltries, 244, 245 
Bartenbach and Richter's process for 

lace and whip leather, 569 
Barton & Co., splitting machines of, 

380 
Base for a high polish to leather, 771 
Bases, 709 

Basic acetate of iron, 98, 99 
of lead, 98, 99 
ferric sulphate for tanning, 135 
sulphate of iron for tanning, 
629 
Bassora gall-nut, 116 
Batchelder's leather blacking, color- 
ing, and dressing machine, 441- 
44^6 
Bate in taweries, preparation of, 650 

stone, 586 
Bating, 262, 335-351 

and final prejiaration for the ooze, 

335-341 
compound of muriate of soda, 
SLiper-tartrate of potassa and 
tartaric acid, 342, 343 
compounds, 341-351 
for glove leather, 649-652 
hides and skins, patents for com- 
pounds for, 351 
in what it consists, 335 
objections to the present method 

of, 336, 337 
period at which the hides and 

skins remain in, 335, 336 
process, Adamson's, 349 
Mullen's, 349 
Soderberg's, 349 
Swan's, 350 
Tucker's, 350 
Tnrley's, 351 
Wilson's, 350 
the theory of, 492, 493 
usual practice of, 337 
various substances used for, 336 
vats and wheels for, 337 



INDEX. 



781 



Bating — 

when used, 335 

Avith blood and ammonia, 285 

with bran, oil of vitriol, and salt, 

345, 346 
with carbolic acid, muriate of am- 
monia, and alum, 343, 344 
with glucose and dried sour cheese, 

346 
with liquor composed of water, 
impregnated with sulphur di- 
oxide previously employed in 
softening and soaking hides, 
346-349 
with muriate of ammonia, either 

alone or with dung, 341-343 
with sulphuric acid and the lime 
liquor in which the skins have 
already been treated for remov- 
ing the hair, 344 
Bauxite, 130 
Bavarian calf-skins, 41 
Bazil, 69 

Beam for whitening, 423, 424 
German form of, 304, 305 
house, 304 

arrangement of in France, 
307 
iinhairing, 304-306 
Beaver, otter, and other skins, tanning 
or coloring with the hair or fur on, 
622-624 
Beech bark, 121 
Beetling, implements for, made from 

very heavj' hides, 43 
Belt knife machine in operation, 496 
splitting machine, 378, 379 
Cummings's improve- 
ment m, 380-383 
Belts, machine, leather for, 692 
Bennat's description of Persoz's 
method of analyzing tanning 
materials, 141 
suggestion for analyzing tanning- 
materials, 142 
Berry's process for softening hides, 

245, 246 
Bichromate of potash, 53, 61, 107 
Bichromates, use of, for tanning, 628, 

629 
Binary colors, 701, 702 
Birch oil, distillation of, 579-581 
manufacture of, 578-581 
products of distillation of, 581 
use of, in the manufacture of 
Eussia leather, 576 



Birch oil — 

poplar, and alder barks, where 
used for tanning, 125 
Bismarck brown, 744 

R for skivers, 751 
Black, 724, 735 

aniline, 744, 746 
an intense, imparting to leather, 
Humphrey's compound for, 
761, 762 
color, 722, 723 
coloring for partly or fully tanned 

skins, Brainerd's, 759 
gloss to leather, compound for 

imparting, 764 
maroon and purple colors to raw 
hides, Merrill and Hoitt's pro- 
cess, 759-761 
Martyn's, compound for leather, 

758 
on alumed leather, 722 
on oil leather, 739, 740 
staining compounds for concealing 
defects in leather, and for ap- 
plying to pocket-books, 762, 
763 
Blacking and smutting appliances, 440- 
449 
brushes, 440, 441 
coloring and dressing machine, 

Batchelder's, 441-446 
compounds, 449-451 

for leather, patents for, 451, 
453 
Hayward's flesh, 449, 450 
leather, 440-453 

patents for apparatuses for. 
449 
Blackings, oil and soap, 449 
Bleaching hemlock tanned and Union 
tanned leather similar to oak 
tannage, 488, 489 
the leather from chamois skins for 
gloves, 688 
Bleu de lumifere, 742 
de Lyon, 742 
de Paris, 742 
de Parme, 742 
Blood, advantages claimed for, in de- 
pilating with, 285 
and ammonia for bating, 285 
lime, and water for depilating, 
284-286 
"Blood stains" on leather, 674 
Blue, aniline, 742 

for skivers, 748 



782 



INDEX. 



" Blue-blaok" tannins, 101 
dark, 734 
for skivers, 752 
on Morocco with aniline, 75(5 
on oil leather, 738 
pale, on Morocco with aniline, 756 
vitriol, 712 
Boarding and graining before the in- 
troduction of machinery, 
431, 432 
by machinery, 431-440 
machine, 432-434 

for Morocco, 438, 439 
Hovey's, 434-438 
machinery, advantages of, 432 
machines, patents for, 439, 
440 
Boettger's proposal to depilate with 
hydi'osulphate of lime, 288 
proposed use of lime that had 
served for purifying gas as a 
depilatory, 275 
Bollman's depilatory compound, 284- 

286 
Bones of the ox, how utilized, 39 
Bonneville method of making artificial 

leather, 72 
Borax, 52 

Bordier's patent, 1842, for tanning by 
means of ferric sulphate, 135 
process for tanning with mineral 
and earthy substances, 627 
Botchford's process of distilling sour 
liquors to get rid of the decaying 
and animal substances in them, 360, 
361 
Bottle green, 730 
Boudet's proposal to depilate with 

caustic soda, 290 
Boxes for exhaust steam and direct 

steam, 216, 217 
Boy den, Seth, early inventor of a split- 
ting machine, 369 
the first to make japanned 
leather in the United 
States, 70 
Bradley's apparatus for purifying ex- 
tracts of bark, 227-231 
Brainerd's compound for coloring 
partly orfully tanned skins, 759 
depilatory, 276 
Brains of calves and sheep for tanning, 

656 
Bran drench for goat-skins, 527 

oil of vitriol, and salt, bating with, 
345, 346 



Branded hides, 55 

Branning for chamois leather, 681, 
682 
injury to skins in, 675, 676 
skins for glove leather, 652, 653 
Breaking hides, list of patents for, 261 
Bromine, 106 

Bronze colors on leather, 766, 767 
dressing for leather, 765, 766 
Brown, aniline, 744 
coffee, 733 
dark, 733 
light, 733 
light leather, 729 
mi-fonce, 730 
mineral pigments, 736 
mixed, 734 
olive, 733 
on oil leather, 739 
Browns, catechu, 733 

for skivers, 751, 752 
Brush for scouring, 385 
Brushed kid finishing, 532 
Brushes, blacking, 440, 441 
Brusliing the dye liquor on the skin, 

730, 731 
Bryant & King's tannery, Woburn, 
Mass., setting machines in use at, 
388 
Bryant's machine for smutting leather, 

447-449, 517 
" B. S." oil for stuffing compounds, 

419, 420 
Bublah, 118 

Buchner on tannomellanic acid, 109 
on Wagner's method of determin- 
ing tannic acid, 152 
Buenos Ayres hides, sweating, 297 

the best hides come from, 40 
Buffido hides, 45 

tanned with chromium com- 
pounds, 61 
Buff' color on leather for pantaloons, 

688 
"Buff" hides," 511 
Buff" leather, 69 

Buffed, grain, and split leathers, 511- 
517 
leather, finishing, 516, 517 
Buffing and whitening machine, 428, 
^429 
the hide for japanning or enamel- 
ling, 592, 593 
wheels, 43 

whitening, and shaving leatlier, 
patents for machines for, 430 



INDEX. 



783 



Bugh's method for tanning beaver, 
otter, and other skins with the hair 
or fur on, 622, G24 
Building for sweating hides and skins, 
293-295 
round leaches, 209-219 
Burdon machine for dressing, setting 
out, and scouring hides, skins, and 
leathers, 401-405 
Burnt alum, 713 
Butea frontosa, 122 
gibsonis, 122 



C.^SALPmiA CORIARIA, 117 
Caesar on the reindeer clothing 
of the German tribes, 37 
Caillelet on the determination of fat 

in leather, 83, 84 
Calcium and sodium as a depilatory, 
27G, 277 
bichromate, 134 
chloride of, how determined in 

the percentage of ash, 82 
hvdrosulphuret as a depilatory, 
275 
preparation of, 288-290 
sulphide and sulphuret for depi- 
lating hides and skins, 283 
sulphuret of, and soda for depi- 
lating, 287 
Calf-skin the best material for parch- 
ment, 68 
uses of, and whence derived, 
41 
Calf-skins, dried, 41 

salted, liming, 264, 265 
split, sometimes used for Mo- 
rocco, 41 
tanned with chromium com- 
pounds, 61 
treating in the limes, 264 
California tanning, interest in, 75, 76 
Calves' brains for tawing, 656 
Camphor and resins, tannins from, 138 
Canada, bark obtained from, 494, 499 
Canary yellow, 724 
Cape, goat-skins of the, 42 
Carbolic acid, 53 

for bating, 336 
for preserving hides, 50 
muriate of ammonia and alum 
as a bating compound, 343, 
344 
used for disinfecting tanner- 
ies, 48 



Carbolic acid — 

valuable as a wash against in- 
fection, 48 
Carbonate of ammonia employed by 
Warrington, 1841, for the pur- 
poses of the bate, 336 
of potassa, 52 
Carbonates, 717-720 
Carbonic acid, 105 
Carbuncles produced by handling hides 

of diseased animals, 48 
Carpene-Barbieri's method of deter- 
mining tannic acid, 143, 144 
Carriage tops, leather noAv and for- 
merly used for, 70 
Carter and Keith's depilatory process, 
270 
process for tanning hides and 
skins with the hair on, and 
for dressing furs, 621, 622 
Cashew-tannic acid, 101 
Catechu brown, 733 

discovery of the tanning proper- 
ties of, 58, 59 
gray-brown, 733 
or terra japonica, 114 
Category of a color, 703, 704 

of a shade, 704 
Cattle breeding one of the principal 
industries in the United States, 
35 
ranches in the United States, 35 
the hides of the improved breeds 
of, less thick and less useful for 
leather, 39, 40 
Caustic lye in the manufacture of cha- 
mois leather, 686 
lime, 710, 711 
soda, depilation by, 290 
Cavalin's process for tanning with bi- 
chromates, 628 
Cellar of an upper leather tannery, 
showing the piles of sides and the 
ma(,'hinery, 368 , 

(Jhalk, ground, 69 

Chamois- and goat -skins, Aikens's 
method of working into glove 
leather, 665 
color, 724 

leather, color of, 688 
colors for, 736-740 
depilation and frizzing for, 

680, 681 
operations in the manufacture 

of, 680 
the most famous, 64 



784 



INDEX. 



Chamois — 

or oil leather, manufacture of, 
679-689 
qualities necessary in, 
679 
or royal leather dyeing, 736-740 
shamony, or shamoy leather, 69 
Chaptal, 58 

Charcoal, depilating with, 279 
Cheese and glucose, bating with, 346 
Chemical compounds, saturation of 
leather with, 553, 554 
examination of vegetable tanning 

materials, 138-164 
reaction which takes place in Pol- 
lock's process of making artifi- 
cial sole leather, 491 
Chestnut bark and quebracho bark 
used for tanning in Eng- 
land, etc., 125 
and quebracho, tanning with, 

129 
where used in tanning, 125 
color on alumed leather, 722 
oak bark, 119 

tan-bark, 483 
Chinese gall-nuts, 115 
Chloride of barium, 61 

how determined in the per- 
centage of ash, 82 
how used in detecting fraudu- 
lent increase in the weight 
of hides, 49 
its use for increasing the 
weight of leather, 86 
of potassium, 61, 62 
of sodium, 61, 62 
Chlorides, 714, 715 
Chlorine, 106 
Chromate compounds, 62 
neutral alkaline, 134 
salts, deoxidizing effect of organic 
matter on, 61 
oxidizing power of, 6L 
Chromates, etc., Heinzerling's method 

of tanning with, 633-641 
Chrome alum in tanning, 629 

leather and tanned leather, stretch- 
ing capacity of, 638-640 
effecl; of boiling in water, 
62 
of steeping in cold water, 

62 
of stuffing with fat or 
parafline, 62 
oxide, 62 



Chrome — 

tanned leather, effect of Immer- 
sion in water, 636-640 
yellow, 736 
Chromic acid, 53, 61, 62, 107, 134 
oxides in tanning, 629 
salts, conclusions of Dr. Clark on 
the power of leather to retain, 
638 
sulphate, 134 
Chromium alum, 132, 713, 714 

the most important of the 

chromium salts thus far 

used in mineral tanning, 1 34 

compounds, tanning and tawing 

with, 61-63 
in chrome tanned leather, 636, 

637 
salts, 133, 134 
sulphate, 131 

withdrawn from chrome tanned 
leather by the action of water, 
636-640 
Chrysaniline, 743 
Circles of normal colors, 703, 704 
Citric acid, 709 

Clark, Dr. J., comparative experi- 
ments of, as regards the sol- 
ubility of tannin in chrome 
leather, 636 
conclusions of, on the power 
of leather to retain chromic 
salts, 638 
on the " degrees of hardness" in 
water, 173 
Clark's modification of Wagner's me- 
thod of determining tannic acid, 
153, 154 
process of determining the hard- 
ness of water by soap solution, 
170 
Classification of sole leathers in the 

United States, 48 2 
Claus's depilatory, 276 
Cleansing and moistening skins for dye- 
ing, 725 
Clements' s leather whitening machine, 

423-426 
Climate, effect of, on the hides of cat- 
tle, 40 
Clothing for man, origin of, 33, 34 
Coal, tannin from, 138 
Coe's process for tanning, 621 

hides and skins Avith the 
wool, fur, or hair on, 
621 



INDEX. 



785 



Coffee brown, 733 

tannic acid, 101 
Cold sweating process, 291-293 
Color, graduated line of, 701 
modified, 701 

of leather, compound for chang- 
ing, 773, 774 
Colored leather similar to our Morocco 
prepared by the ancient 
orientals, 65 
spolten of by Ezekiel, 56 
various phices in which it has 
been manufactured, 66 
Color! metric method of determining 

tannic acid, 142 
Coloring and polishing leather, com- 
pounds for, 758-775 
compounds for, patents 
for, 775 
and tanning beaver, otter, and 
other skins with hair or fur 
on, 622-624 
hides and skins with hair and 
fur on, 620-626 
blacking, and dressing machines, 

441-446 
Klemm's oil leather, 694 
leather with aniline upon a starched 
surface, witli an appearance sim- 
ilar to marble paper, 768, 769 
pai'tially tanned hides and skins, 

773 
polishing, and water - proofing 
leather, composition tor, 771, 
772 
preparing, and polishing light 
skins for car seats, etc., 770 
Colors all derived by reflection from 
the different colors of which 
the white light or sun light is 
composed, 698 
aniline, used in aqueous solutions 

preferable for leather, 740 
normal circle of, 703, 704 
of the spectrum can be artificially 
produced by three artificial dye- 
stnlis, 701 
requiring firing, treatment of, 726 
transition of through their count- 
less modifications, 703 
Composition as a base for a high polish 
to leather, 771 
for impregnating hides and skins 
and preserving them in condi- 
tion to be unhaired by immer- 
sion in water, 50-52 
50 



Composition — 

for polishing, water-proofing, and 

coloring leather, 771, 772 
for treating japanned leather and 
producing an imitation of alli- 
gator skin, 594 
Compositions for patent japanned or 

enamelled leather, 590, 592c 
Compound for changing the olor of 
leather, 773, 774^ 
for finishing upper leather. 450 
for renewing the surface of japan- 
ned leather, 592 
for whitening leather, 7 74 
Compounds and materials for tanning 
and for tawing leather and for 
preparing raw hides, especially 
claimed or mentioned in an^- 
patent, 616-619 
for coloring and polishing leather, 

758-775 
for producing imitation of grain 

or Morocco leather, 551-555 
for stuffing and currying leathei', 
patents for, 420 
Conductors to the leaches, 218, 219 
Connective tissue of skin, behavior of, 
toward certain sub- 
stances, 99 
formula of, 99 
qualities of, 99 
Contagious diseases, hides of animals 
having died of, dangers in handling, 
48 _ 
Contrivance for cutting bark prepara- 
tory to peeling, 178-181 
Conveyer, bark, 200-202 
Coogan's boarding and graining ma- 
chine, 432-434" 
Copal varnish, 69 
Copper, 53 

suljjhate of, 52 
Coralline, 746 

on« Morocco, 756 
Cordovan leather, 65. 66 

whence the name is derived, 
65 
C.ordillot's process for coloring blac]*: 

with aniline, 745 
Coriin, 94 

formula of, 84, 85, 98 
qualities of, 97, 98 
to obtain, 97 
Corium or leather skin, composition 

of, 94 
Counter fleshing the hides, 310 



786 



INDEX. 



Coupe's stretcLing machine, 568, 569 

Cream of tartar, 717 

Creasing machines, patents for, 465- 

467 
Creasote, 53 

Crimson, aniline for skivers, 749 
Crockett, David, of Newark, N. J., 
the first to manufacture enamelled 
leather in the United States, 70 
Crown leather, capacity of, to resist 
water, 692 
for machine belts, 692 
softness of, 692, 693 
strength of, 691, 692 
weight of, 691 
Cryolite, 130 
Cube alum, 713 
Cummings's improvement in belt knife 

splitting machines, 380-383 
Cupiic acetate, 716, 717 

its use in precipitating tannic 
acid when testing for grape 
sugar, 86 
chloride, 98 
sulphate, 712 
Curing hides. Rock's liquid for, 52, 

53 
Curriers' knives, 423, 424 

patents for machines for 
sharpening, 430 
slickers, patents for, 430 
Currying business in twelve States, 80 
establishments in the United 

States, 79 
leather, patents for compounds 

for, 420 
tallowed leather, 523 
Cutch, gambir and bark, imports and 
exports of, 79 
where used in tanning, 1 25 
Cuticle or epidermis, 93 
Cutlery manufacture, buffing wheels 
for, made from very heavy hides, 43 
Cutting bark preparatory to peeling, 
contrivance for, 178-181 
surface of leather a test of tan- 
ning, 85 



D'ARCET'S recommendation of 
tanning with ferric salts in the 
last century, 135 
Daheny's table for leather scouring 

machines, 405-407 
Dahlia, 74 2 

imperial, 742 



Daigneaii's contrivance for cutting bark 

preparatory to peeling, 178-181 
Damaged hides, 55 
Daniels's tan press, 508 
Danish glove leather, 668, 669 
Dark blue, 734 
brown, 733 
gray, 735 
green^ 733 

rose pink for skivers, 750 
Davy on the tannin in beech bark, 121 
Davy's examination of the epidermis 
of the bamboo and sugar cane, 
175 
experiments on the tannin in oak 
bark in the spring and fall, 177 
method of determining tannic 
acid, 139 
Decaying animal and vegetable sub- 
stances in liquors, 360 
Deer-skins, 45 
Defects of alumed varieties of leather, 

673-679 
Degras obtained from the waters of 
wool factories, 418, 419 
the residue obtained from the 
tanning of buck, goat, and 
sheep-skins, 419 
Delane's method of salting hides, 49, 50 
De Montoison's depilatory process, 270 
Denmark, origin of horse leather in, 

572 
Depilating, action of lime and sulphur 
in," 28 3 
and removing grease with a com- 
pound of water, lime, soda ash, 
saltpetre, and flowers of sul- 
phur, 281 
and swelling hides with sulphu- 
retted hydrogen gas, with lime, 
soda, etc., 273, 274 
by caustic soda, 290 
by stacking in heaps, 301 
by sulphuret of calcium and soda, 

287 
by sweating, 291-300 
by the use of soda-ash, caustic 
lime, monosulphuret of potas- 
sium, hard soap, and soft water, 
271, 272 
composition of nitrate of potassa, 
chloride of sodium, sulphuric 
acid, and tartaric acid, 272, 
273 
compound of potash, lime, salt, 
sulphur, and charcoal, 274, 275 



INDEX. 



787 



Depilating — 

hides and skins, patents for com- 
jDOunds for, 302, 303 

processes and compounds 
for, 2 G 1-303 
softening and plumping, hides and 
skins with sulphide of barium, 
282, 283 
use of "refuse gas lime" in, 275 
with acid liquors, 2G5 
with charcoal, 277 
with double sulphate of sodium 

and calcium, 276, 277 
with lime, 261-269 
with slacked lime and ashes, 265 
with water, burnt oolite, and 

muriatic acid, 284 
with water In an open vessel, 286, 
287 
lime, and blood, 284-286 
with sulphide and sulphuret of 
calcium, 283 
Depilation and frizzing for chamois 
leather, 680, 681 
and liming for glove leather, 648 
by maceration among barbarous 

tribes, 37 
by the hydrosulphate of lime, 288 
Depilatory methods now nearly obso- 
lete, 300-302 
of lye from wood ashes or potash, 

lime, etc., 278-281 
of potash, lime, and orpiment, 

288 
process, Carter and Keith's, 270 
De Montoison's, 270 
Head's, 270 
Robinson's, 269 
Ward's, 269 
Wilson's, 270 
Desmond, 58 

Determining the constituents of water, 
metirod for, 169-173 
the tannic acid in tanning mate- 
rials, 139-164 
Dewees and Green's stuffing com- 
pound of "B, S. oil," 419, 420 
Dextrine for tawing, 656 
use of in bating, 346 
Dicing machines, patents for, 465-467 
Digallic acid, 108 
Dinitro-naphthalene, 747 
Dirty chamois leather to clean, 688, 

68"'9 
Diseases of lambs and sheep, effects of, 
on leather, 674, 675 



Disinfecting tanneries, importance of, 

48 
Distaff" and the loom, early use of, 36 
Distillation of birch oil, 579-581 
of sour tan liquors, 360, 361 
Divi-divi, 117 

leather tanned with, qualities 
of, 117 
Dog-skin, 44 
Dog-skins, Watts' s method of working 

into glove leather, 666 
Domine's method of exhausting gall- 
nuts, 105 
Donath on quebracho, 122 
Donath's test of aluminium sulphate, 

131 
Dressing and finishing chamois leather, 
685-689 
blacking and coloring machine, 

441-446 
furs, Carter and Keith's process 

for, 621, 622 
setting out and scouring machine, 

Burdon, 401-405 
sheep-skin fleshers for glove bind- 
ings, etc., Hart's process, 557, 
55"8 
sheep-skins, Hesthal's process for, 
560, 561 
Drum, revolving, for handling hides, 

357 
Dryers for patent leather, 590 
Dry flint hides, 54 

sweating, 291 
hides, soaking, 237, 241 

in running water, 243 
sunburned, weather-beaten, 

or moth-eaten, 55 
treatment of in France, 242 
working and softening in the 
hide mill, 242 
salted hides, 54 
Drying and striking out skins for 
"Morocco, 530 
loft of a Morocco factory, showing 

the skins hung up, 530 
loft of a sheep-skin tannery, 586 
the skins after softening, 732 
yard, with the sides of leather 
hung over the poles, 496 
Dubbing, water- proofing, and whiten- 
ing upper leather, 504-507 
Dudley and Brooks's process for hand- 
ling goat-skins, 529 
Dung bating, the theory of, 336 
use for bating, 335, 336 



INDEX. 



Djar's process for preparing, coloi-ing, 
and polishing light skin for car seats, 
trunk covers, etc., 770 
Dye, applying, 730 

for Russia leather, 576, 578 
liquor, brushing on the skin, 730, 

731 
liquors, mother, preparing for 
glazed leather, 729 
Dyeing alumed leather, 721-732 
by dipping, 723, 724 
by paintin'g, 724-732 
chamois or royal leather, 736- 

740 
glazed leather, 724 
glove leather, 721 
Grenoble method of, 724, 725 
leather, 698-758 

by means of a Vanadic com- 
pound, 764, 765 
general remarks on, 698-705 
Russia and Morocco leathers with 

aniline colors, 754-758 
skins on the grain side, 723 

on the flesh side, 721-723 
sumach-tanned skivers with ani- 
line colors, 748-754 
with aniline colors, and the 
methods of their preparation, 
740-748 
wool on sheep-skins, Jack's 
method and machine for, 624- 
626 
Dyer's art, importance of, 700 



EAST INDIA kino, 114 
Indies, goat-skins of, 42, 43 
Eaton's process of depilating hides, 

271, 272 
Eddlemon and Walker's polish for 
leather, used for bags, satchels, etc., 
772, 773 
Edwards, Wm., the inventor of the 
hide mill and of the rolling contri- 
vance now employed for rolling sole 
leather, 252 
Egg, white of, for glazing glove 
leather, 663, 664 
yelk of, for tawing, 654-657 
Eitner's directions for the use of ani- 
line colors, 754-758 
experiments on the eifect of differ- 
ent inorganic consituents of 
water upon the depilated skin. 
167 



Elephant hides, 44 

Ellagic acid, 107 

Elm bark, 319 

Ely's process for plumping before de- 

jpilating, 246-250 
Emeraldine, 743 

Enamelled, japanned, and patent 
leather, patents for, 595, 596 
leather, 69, 70 

first manufactured for car 
riage tojDs in the United 
States, by David Crockett, 
of Newark, N. J., 70 
England's apparatus for handling 
hides, 353-356 
paddle wheels for handling hides, 
337, 355, 356 
England wheel, use of, 512, 518 

wheel, advantages of, 356 
English method of dyeing, advantages 
of, 725 
by painting, 725, 726 
patents for mineral substitutes for 
vegetable tanning, early, 626 
Enos and Clements' s leather whitener, 

424 
Enos's attachment to splitting machine 
to prevent injury to the arms of 
workmen, 371-375 
tanning process, 599 
Epidermis, composition of, 93 
of bark, 174 
of the bamboo and the sugar cane, 

Davy's experiments on, 175 
useless to the tanner, 94 
Erlanger leather, branning, 652, 661 
finishing, 661-668 
liming and depilating for, 649 
method of soaking and rinsing 

for, 647 
tawing pastes for, 653-661 
treatment in bate of dogs ex- 
ci-ements for, 649-652 
or French method of tawing, 642- 
668 
Ether, 698 

extracting resinous substances 

from leather with, 127 
use of, for exhausting gall-nuts, 
104 
Ethyl rosaniline gi-een, 743 
Eucalyptus, bark of, 122 
Eureka bark mill company, rolling 

machine of, 485, 486 
Eurojie, hilly regions of, the coat-skins 
of, 43 



INDEX. 



European galls, 115 

Evans's artificial leather company, the 

leather produced by, 73 
Evans's imitation sheep-skins, pi'epara- 

tion of, 561-563 
Evaporator, McKenzie's, 230 
Evening or making leather of uniform 

thickness, patents for, 557 
Examination of leathers, 81-92 

of vegetable tanning materials, 
chemical, 138-164 
Extract, horse-chestnut, 120 

of hemlock bark, American, 119 
Extracthig tannin, the best method, 203 
Extractive matter removing from 
tanned leather, 503, 504 
substances, influence of, on the 
value of a tannic acid, 113 
Extracts from tan- bark, patents for, 
235, 236 
of bark, purifying, 227-231 
Ezekiel's description of the dresses 
and harness of the Babylonians, 
etc., 57 



FACTS and principles in the 
sciences and arts, 56 
Fagus silvatica, 121 
Fair finished leather, 41 

leather, 70 
Farnham's composition of glycerine, 
resins, etc., as a base for a high 
polish to leather, 771 
Fast brown for skivers, 752 
red R for skivers, 752 
Fat and resin in leather, determination 
of, 81, 82 
jjercentage of, in leather, detei'- 
mination of, 83, 84 
Fats used for tawing, 64 
Feed i-olls for unhairing machines, 
McDonald's improvement in, 325- 
327 
Fehberg's volumetric denomination of 

tannic acid, 140 
Fehling, Prof., method of determining 
tannic acid, satisfactory re- 
sults obtained by, 143 
on Klemm's process, 695 
Fehling' s method, modified by Miiller, 

142, 143 
Fennessy's bronze dressing for leather, 

765, 766 
Fermentation of tannic acid in unclean 
tanneries, 112 



Ferric acetate, 715 

in tanning, 629 
aluminium in tanning, 629 
chloride, 98, 714 
citrate, 142 
nitrate, 714 
salts, 135 

" blue-black," tannins which 

precipitate, 101 
" green," tannins which pre- 
cipitate, 1 01 
Knapp's processes of tanning 

with, 628-633 
tanning with, 626, 627 
sulphate for tanning, 627 
in tanning, 628 

advantages claimed for, 
630 
Pfanhauser's process for pre- 
paring and tanning with, 
628 
Ferrous sulphate, 131, 711, 712 
Fibroin, 99 
of silk, 99 
of skin, 99 
Filling and running the leaches, 219- 
226 
cup for Morocco manufttcturers, 
Walters' s, 539-541 
Filtering tanning liquor for purposes 
of determining tannic acid, 140 
water through exhausted tan, 
112 
Fine grades of leather, laying away, 

366, 367 
Finishing and dressino- chamois leather, 
685-689 
and pebbling machine, Knox's, 

464, 465 
butr leather, 516, 517 
brushed kid, 532 
glove leather, 661-668 
grain leather, 515, 516 
imitation French kid, 531, 532 
machines, patents for, 465-46 7 
oil goat, 535 
pebble- grain goat, 535 
polishing, glassing, pebbling, roll- 
ing leather, etc., machines for, 
453-468 
split leather, compound for, 451 
straight grain goat, 532, 533 
the side of heavy upper leather, 

details of, 497-500 
the split, 500 
upper leather, compound for, 450 



^90 



INDEX. 



Fiorillo's method for applying aniline 

bronze color to leather, 766, 76 7 
Fir bark, 118 
Fischerstroern's method of distilling 

birch oil, 579 
Fish oil, 70 

Fitting the colored split, 500 
Fitzhenry's leather dressing machine, 

398-401 
Flanders and Marden's splitting ma- 
chine, 369 
Flaying skins and hides, important 

points to be considered in, 46 
Fleck and Wolff's method of deter- 
mining tannic acid, 141 
Flesh blacking, Hayward's, 449, 450 

color, 735 
Flesher, saw-tooth for dry hides, 309 

the, 308 
Fleshing and iinhairing, 304,' 335 
by machinery, 313-333 
hides and skins simultaneous- 
ly, Janson's machine 
for, 330-332 
the most laborious ope- 
rations in tanning, 313 
machines, patents tor, 333- 
335. 
a sure hand required in, 311 
by the hand process, 308-311 
knife, German, 308 
macliines not generally in use, 
313 
objection to, 311 
slating, and striking out machines, 
Eoberts and Lenox's, 332, 
333 
the hide, the details of, 309-311 
working, and unhairing hides and 
skins, Taylor's machine for, 
327-329 
Flinting machines, patents for, 465- 

4G7 ^ 
Fluffing and grinding machines, pa- 
tents for, 556 
Fluids for leaching, apparatus for the 

automatic distribution of, 204-208 
France and Italy, lamb-skins of, 42 
arrangement of the beam house 

in, 307 
attention paid to the beam work 

on calf-skins in, 306 
unliairing and flesliing as jjrac- 
tised in, 306, 307 
Fraude, aspidospcrma found .by, in 
the baric of quebracho, 122 



Fraudulently increasino- the weight ot 
hides by employment of sulphuric 
acid, 49 
Fraser's experiments with tanned 

leather and chrome leather, 639 
Freely's method of manufacturing ar- 
tificial Russia leather, 582 
French beams, 307 

"boarding" contrivance, 732 
kid, imitation, finishing, 531, 
532 
■ method of dyeing glazed leather, 
726-729 
or Erlanger leather, precautions 
to be taken in making, 
642 
method of tawing, 642-668 
division of processes, 

647 
in Germany and 
Austria, 642 
sumach, 116 
whitening slicker, 423 
Fresh liides, sweating, 299, 300 

salted hides not generally sweated, 
299 
Friend and Annable's improvement in 

hide-mill, 253-255 
Friend's glassing machine, 468-460 
" Frieze," cause of during the process 

of sweating, 291 
Frizzing and depilation for chamois 

leather, 680, 681 
Fuchsine, 743, 744 
Fuel of spent tan, 507 
Fulling chamois leather in the oil, 682- 
685 
drum, Knapp's, for tanning, 630- 

632 
glove leather, 650 
in of insoluble soaps of ferric 

oxide, etc., in tanning, 628 
iron soap into the skin by Knapp's 

process, 630, 631 
machine, the resemblance of the 

hide-mill to, 252 ' 
process, the, represented on tomb 
of Beni Hassan in Egypt, 252 
Fulton's tanning process, 599 
Fur and hair, tanning and coloring 
hides and skins with the, on, 620- 
626 
Furs, dressing, Carter and Keith's 
process for, 621, 622 
to color, 624 
Fustic, 118 



INDEX. 



Wl 



GALLIC ACID, 108 
formation of, 102 
Gall-nut, tannin of the, 103 
Gall-nuts, 114, 1.15 

Chinese, 115 
the best imported, 115 
to exhaust, 104, 105 
Gallotannate of potash, 109 
Gallotannic acid, 101, 103 

constitution of, 108, 109 
experiments of Sehriff in re- 
gard to, 108 
extraction of, 103 
Galls, 115 

green, 115 
Gambler, 114 

cutch and bark, imports and ex- 
ports of, 79 
its use in tanning in Great Britain, 

125 
liquor, treatment of hides for 
patent leather with, 587 
Garge's tanning process, 602 
Gas lime refuse as a depilatory, 275 
what composed of, 275 
works, waste water from, for soft- 
ening dry hides, skins, and pel- 
tries, 243-245 
Gassincourt on the tannin In tormentil 
root, 122 
on the tannin in alder bark, 121 
Gelatine, precipitation of with tannin, 

139 
Generator for preparing hydrosulphate 

of lime, 288-290 
Gerber on quercus bitter. 111 

on the substances contained in an 
aqueous solution of the inside 
layer of oak bark, 139 
Gerland's method of determining tan- 
nic acid, 144 
German calf-skins, 41 
fleshing knife, 308 
harness leather, 518 
tribes, reindeer clothing of, 37 
Germans, leather ships of the ancient, 

57 
German's tanning process, 598 
Germany and Austria, French or Er- 
langer leather, tawing in, 642 
steeping cisterns In, 312 
Geum urbanum, 122 
Gilding and ornamenting leather for 
suspender ends, 765 
leather, 765 
Glac6 leather, 664 



Glassing and rolling brushed kid, 532 
leather by hand with a glass slicker, 
453 
by machinery, 453, 459 
machine. Friend's, 458-460 

Hildreth's, 460, 461 
machines, patents for, 465-46 7 
or polishing, pebbling, finishing, 
rolling leather, etc., machines 
for, 453-468 
Glauber salt for salting hides, 50 
Glazing inferior qualities of glove 
leather, 663, 664 
machine. Baker's improved, 462, 
463 
overhead for Morocco, 464 
machines, patents for, 465-467 
pony machine. Baker's, 463, 464 
Glove binding, etc., sheep-skin fleshers 

for, 557, 558 
Glove calf, 525 

how long it remains in the 
limes, 526 
leather, Aikens's method of work- 
ing lamb-skins Into, 664, 
6 6' 6 
Danish, 668, 669 
dyeing, 721 . 
Norwegian, elm bark used 

for tanning, 119 
skin for working, 647 
Watts' s method of making, 

666, 667 
willow bark used for tanning 
Swedish, 121 
sheep, 525 

how long It remains in the 
limes, 526 
Glucose and dried sour cheese, bating 

with, 346 
Glueoside, pyrogalllc, 109 

Strecker on tannin as a, 106, 108 
tannin not a, 107 
Glue factories, phosphoric acid of, for 
bating, 349 
percentage of, in leather, 128 
stock, hides which are classed as, 

55 
what made of, 39 
white, use of, in determining tan- 
nic acid, 143 
Glycerine, 53 

and carbolic aeid, mixtures of, 

preserving hides, 50 
resins, etc., as a base for a high 
polish to leather, 771 



792 



INDEX. 



"Glycerole" of egg, 417, 418 
Goat and chamois skins, Aikens's 
method of working into glove 
leather, 665 
and sheep-skins, tanning apparatus 

for, 536-545 
oil, finishing. 535 
pebble-grain finishing, 535 
straight graining and finishing, 

532-535 
skin bags, filling with the sumach 

liquor, 527-529 
skins for Morocco leather, classifi- 
cation of, 524 
how long they remain in the 

limes, 526 
placing in the tanning liquor, 

527" 
whence generally obtained, 

and uses, 42, 43 
Watts' s method of working 
into glove leather, 666 
Gorsline's apparatus lor handling hides 

and skins, 387 
Gouget on the origin of the art of tan- 
ning, 37 
Gould's tanning process, 599, 600 ' 
Graduated line of color, 701 
Grahowsky and Oser on the formula of 

quercotannic acid, 110 
Grain, artificial, Patterson's process 
for forming on the hide, 593, 
594 
leather, finishing, 515, 516 
or Morocco leather, imitation of, 
compounds for producing, 551- 
556 
split and buff" leathers, 511, 517 
where manufactured. 
511 
Graining and boarding by machinerj', 
431-440 
machine, Coogan's, 432-434 
•Hovey's, 434-438 
for Morocco, 438, 439 
machines for, 440 
board for graining Morocco by 

hand, 534 
machine for Russia leather, 578 
Grape sugar, its use for increasing the 

weight of leather, 86 
Grassi's method of determining tannic 

acid, 150, 151 
Grauhe on determining tannic acid, 

142 
Gray, 723 



Gray — 

brown catechu, 733 
dark, 735 
iron, 735 
Grease, machine for removing, from 
leather, 421, 422 
patents for machines for removing 

grease from leather, 422 
' removing with a compound of 
water, lime, soda ash, saltpetre, 
and flowers of sulphur, 281 
Green, aniline, 742, 743 

brilliant, for skivers, 753 
dark, 733 
hides, 54 

soaking, 23 7 
on Morocco with aniline, 756 
on oil leather, 738, 739 
picric, 733 

Russia, for skivers, 753 
salted hides, 55 
sap, 734 
shade, 724 
shaving hides for upjier leather, 

312 
stock, laying, 366 
"Green" tannins, 101 
Green, Victoria, for skivers, 750 

vitriol, 711, 712 
Greens, olive, 733 

Grenoble method of dyeing, 724, 725 
Grinding, cutting, crushing, and con- 
veying tan-bark, 184-202 
of bark, importance of, 184 
Grounding and fluffing machines, pat- 
ents for, 550 
Grouvelle and Duval- Duval's process 

of distilling birch oil, 580, 581 
Gum arable in tawing, 655 



H.5:MAT0X YLON Campeachia- 
num, 118 
Hair and fur, tanning and coloring 
hides and skins with the, on, 
620-626 
and wool fabrics, early felted, not 
woven, 36 
industries, 36 
bulb, 95 
follicle, 95 

of the ox, how utilized, 39 
papilla, 95 
primitive manner of removing 

263 
sacks or roots, 95 



INDEX. 



793 



Hallwaelis on Mittenzweis's method 

of determining tannic acid, 150 

on determination of tannic acid, 

143, 144 

Halsey's combined vat and wheel, 529 

wheel and vat for tanning 

Morocco, 542-545 

Hamburgh, manufacture of horse 

leather in, 572, 573 
Hammer's method of determining tan- 
nic acid, 144-146 
Hammond's process of soaking hides 
and skins with the use of saltpetre, 
239, 240 
Handler rocker, 353 
Handling and plumping, 352-3fi3 
apparatus, Gorsline's, 357 
appliances, patents for, 358, 359 
heavy stock before laying away, 

368 
hides and skins, 352-359 

England's apparatus for, 

353—356 
improvements in. 352 
in the lime pits, Steinmann's 

apparatus for, 266-269 
methods of, 352, 353 
Steinmann's apparatus for, 
357 
in the interior of a large revolving 

drum, 357 
processes still in use in Europe, 

356, 357 
sides for pebble and grain leather, 
357 
Hardness of water, process of determin- 
ing by a soap solution, 170 
total, determination of, 171- 
173 
permanent, of water, determina- 
tion of, 173 
Harness leather, dyeing with aniline 

colors, 757, 758 
Hart's process for dressing sheep- skin 
fleshers, glove bindings, etc., 557, 
558 
Hatcher's tanning process, 600 
Havana brown, 744 
Hay ward's flesh blacking, 449, 450 
Hazel color, 724 

H B crown leather, Preller's, 691-693 
Head's depilatory process, 470 

process for soaking, liming, tan- 
ning, blacking, and gumming 
hides for upper leather, 500- 
603 



Heavy leathers sold by weight, 468 
stock, handling before laying 

away, 368 
upper leather, 492-503 

details of the tanning of, 

495-507 
finishing the side of, de- 
tails of, 497-500 
Heinzerling's leather, experiments 
"with, 636-640 
working into shoes, 636 
method of determining the tan- 
ning constituents in leather, 
82 " _ 
of tanning with chromates, 
633-641 
mineral tanned leather, ability of, 

to resist water, 87-89 
process, mineral constituents in 
leather tanned by, 85 
of tanning, or tawing with 
chromium compounds, 61- 
63 
Hemlock and oak barks, astringent 
principle of, the sanie, 
481, 482 
general use of, in the 
United States, 598 
bark, 118, 119 

American extract of, 119 
consumed in tanning in the 

United States, 75 
qualities of, 118 
the liquor yielded by a cord 

of, 221 
use of, in the United States, 
125 
sole leather, varieties of, 482 
tanned and union tanned leather, 
bleaching, 488, 489 
leather, 481 

grading of, 482 
the coloring matter and resin m, 
481 
Henry's depilating compound, 274, 275 
Hermstadt, 58 

Herodotus on the clothing of the tribes 
of the Caspian Sea, 37 
on the early use of sheep-skin for 
writing on, 57 
Hesiod on leather shoes lined with fur, 

57 
Hesthal's process for dressing sheep- 
skins, 560, 561 
Hibbard's process for preparing and 
tanning sheep-skins, 559, 560 



794 



INDEX. 



Hibbard's — 

tannino- pi'ocess, 598, 599 
Hide mill, improvement in, by Friend 
and Annable, described, 
253-255 

invented by Wra. Edwards, 
Northampton, Mass., in 
1812, 252 

Middleton's, 258-260 

the idea of, due to fulling 
machine, 252 
mills, 250-2C0 

differ greatly for the various 
branches of leather, 250 

for Morocco leather, 250, 251 

in common use, 252, 253 

patents for, 260 
Hides and skins, 33-55 

coloring, partially tanned, 
773 

composition for preserving, 
50 

consumed in the United 
States, 75 

criteria to 2;uide the purchaser 
of, 47, 48 

depilating, 261-303 

historical notes on their early 
uses by man, 33-38 

importance of removing from 
slaughtered animals imme- 
diately, 45 

important points in flaying, 46 

injuries to, in soaking, 238 

Napier's process for preserv- 
ing, 53 

of animals which have died of 
contagious diseases, dan- 
gers in handling, 48 

origin of their use by man, 
33, 34 

removing from animals, 45- 
47 

Sabath6 and Jourdan's pro- 
cess for preserving, 53 

Slice's process of preserving, 
53 

selecting, 47, 48 

unhairing them by the same 
composition with which 
they are impregnated for 
preserving, 50-52 

varieties of, used for leather, 
38-45 

washing and soaking, 237- 
243 



Hides and skins — 

AVickersheimer's process of 

preserving, 53, 54 
with the hair and fur on, tan- 
ning and colorinnf, 620-626 
with the hair on. Carter and 
Keith's process for tanning, 
621, 622 
breaking, list of patents for, 261 
classified as dry flint, dry salted, 
green, green salted, and part 
cured, 54 
commercial classification of, 54 
dry, are damaged when sun- 
burned, weather-beaten, or 
moth-eaten, 55 
soaking in running water, 243 
for buff" leather, preparation of, 

511 
for German harness leather, 518 
for grain, split, and buff" leathers, 

511 
for leather, whence the American 
supply is, and in the future will 
be, drawn, 40 
for upper leather, Head's process 
for soaking, liming, 
tanning, blacking, and 
gumming, 500-503 
whence obtained, 494 
fraudulently increasing the weight 

of, 49 
from Buenos Ayres and Monte- 
video, difference in, 40 
from Rio Grande, 41 
Glauber salts for salting, 50 
importance of preparing in the 

beam house, 263 
indications of their readiness for 

scouring after soaking, 312 
influence of hard water on, 98 
known by the port from which 

they are shipped, 40 
Lampert's apparatus for working, 

338-341 
liming of, too long continued, 

gives poor weight, 98 
MacBride's discovery of the use 
of sulphuric acid for swelling, 58 
number of, consumed in Russia, 

66 
of cattle, how affected by sudden 

changes of temperature, 40 
of the improved breeds of cattle 
less thick and less useful for 
leather, 39, 40 



INDEX. 



795 



Hides — 

or skins, with the wool, hair, or 

fur on, 621 
parts of, how classed, 38 
preparation of, for heavy upper 

leather, 494, 495 
preparing for Klemm's oil leather, 

693 
preserving, 49-55 

list of patents for, 54 
Rock's process for preserving, 52 
salting, 49, 50 

skins, and bark, exports and im- 
ports of, 79 
and peltries, processes for 
softening, 243-246 
soaking after ileshiiig, the length 

of time for, 312 
South American, how classified, 
wlience received, and their qual- 
ities, 40, 41 
swelling or plumping, 167 
tests for detecting sulphuinc acid 
when fraudulently used for in- 
creasing the weight of, 49 
the skins of the larger animals, 38 
the uses to which different kinds 

are put in making leather, 41 

those that are stag, or tainted, 

and badly scored, grubby, or 

murrain, rank as damaged, 55 

which are classed as glue stock, 

55 
with the hair on, Pingree's process 
for tanning, 620 
Hide-workino- machine, the Holmes, 

392-398 
Hildreth's glassing machine, 460, 461 
Hippopotamus hides, 44 

tanned witli chromium com- 
pounds, 62 
Historv of tanning, svnopsis of, 56- 

63 
Hoev's compound for renewing the 

surface of japanned leather, 592 
Hoffman's putting out machine, 545- 
550 
violet, 741 
Hog-skins, 44 
Holbrook's process for preparing tan 

bark for use, 197-200 
Holmes's improved scouring machine 
parts, 396, 397 
scouring, setting, and hide-work- 
ing machine, 392-398 
tan press, 507, 508 



Holtz's apparatus for obtaining a pure 
and readily soluble tannin, 232-234 
Homer has perpetuated the name of a 
tanner who showed kindness to 
him, 57 
on the boots of Agamemnon, 57 
Horse-chestnut bark, 120 

extract, 120 
Horse-hides, whence obtained, and 

their uses, 43 
Horse leather for foot wear, 572-574 
manufacture of, by Preller's 

method, 693 
origin and manufacture of, in 
Denmark, 572 
Hovey's boarding and graining ma- 
chine, 434-438 
Howell & Co. the only exhibitors of 
Russia leather at the Centennial, 
575 
Humphrey's compound for imparting 
an intense black to leather, 761, 762 
Hungarian leather, history of, 68 
Hungarians celebrated at an early date 

for their white leather, -64 
Hvdrates of potassium and sodium, 

'709, 710 
Hydrochloric acid, 105, 107, 707, 708 
bating with, 336 
its employment in determin- 
ing lime in leathei-, 82, 83 
its use in determining the 
percentage of fat in leather, 
83 
property of dissolving lime 

possessed by, 336 
use of, in separating coriin, 
97, 99 
Hydrometer, the, 221, 226 
Hydrosulphate of lime as a depilatory, 
288 
preparation of, 288-290 
Hydrosulphuret of calcium as a depi- 
latory, 275 
preparation of, 288-290 



ILLINOIS, tanning interest in, 75, 
76 
Imitation alligator skin, 594, 595 
French kid, American, 525 
finishing, 531, 532 
of grain or Morocco leather, com- 
pounds for producing, 551-555 
Improved methods for tawing and 
dressing sheep-skins, 558-561 



^96 



IKDEX. 



Improvement of an art, the means for, 

5G 
Improvements in tan presses, 507— 

511 
Increasing the weight of hides by the 

employment of sulphuric acid, 49 
Indigo solution, preparation of, for 

determination of tannic acid, 154 
Injuries to hides and skins in soaking, 

238 
Injury to skins in branning, 676 
Inorganic acids, action of, on skin 

fibre, 100 
Inside sole leather tanning, 486, 487 
Intercellular substance in skin, 97 
Iodic acid, 106 
Iodine, 106 

use of, in determining tannic acid, 
144 
Iron, 53 

alum, 132 

in tanning, 629 
basic igulphate of, for tanning, 629 
gray, ^73 5 

soap fulling into the skin by 
Knapp's process, 630, 631 
Knapp's, in tanning, 630 
of Prof. Kntipp, 135 
sulphate of, 52 
Irons, flat, polishing glove leather with, 

663 
Ii'ons's tanning process, 598 
Isinglass, use in determining tannic 

acid, 143 
Italian sumach, 116 
Italy and France, lamb-skins of, 42 
the tanning industry in, 7 7, 78 



JACK'S method and machine for 
dyeing wool on sheep-skins, 624- 
626 
Jacob and Laban, early transactions 
between, 34 
a shrewd cattle trader, 34 
Jager's process of producing colors on 
leather with oxalic acid, salt of tin, 
etc., 767, 768 
Janson's machine for simultaneously 
unhairing and fleshing hides and 
skins, 330-332 
Japanned, enamelled, and patent 
leathers, patents for, 595, 596 
leather, in imitation of alligator 
skin, 594, 595 
mixtures for, 590, 591 



Japanned leather — 

renewing the surface of, 592 
or enamelled leather, preparing 
the cut surface of split leather 
for manufacturing, 592-594 
patent and varnished leathers, 70 
Japonica and other highly concen- 
trated tanning agents, effect of, on 
the leather, 482 
Jeans' s method of determining tannic 

acid, 144 
Jenkins's tanning process, 606, 607 
Jenninos's artificial tanning material, 
136, 137 
method of tawing, 669-673 
tawing process, theory of, 672, 
673 
Johnson's apparatus for the automatic 
distribution of fluids for leach- 
ing, 204-208 
process for tanning light skins 

with the hair on, "620,'" 621 
sprinkler for leaching, 205-208 
Juglands regia, 119 
Juncten, 70 

Junior's method for manufacturing 
lace leather, 565-56 7 



KANGAROO leather, 583 
skins, leathers from, uses and 
where made, 45 
Kathreiner on Jeanes's method of de- 
termining tannic acid, 144 
on Lowenthal's method of deter- 
mining tannic acid, 157 
on the tannic acid in tanning ma- 
terials, 158 
Kathreiner's conclusions as to Lowen- 
thal's method of determining 
tannic acid, 159 
directions for obtaining a correct 
sample of oak bark for ana- 
lysis, 160 
Keeler's tanning process, 599 
Kennedy's tanning process, 600, 601 
Kester's experiments on the quantities 
of tannin of various kinds absorbed 
by skins, 126 
Kid- and lamb-skins, assorting, 6 44 

prices and qualities of, 
644 
brushed finishing, 532 
Kid-skins for glove leather, 643 

putrefaction of, 644, 645 
Kidder's tanning process, 606 



INDEX. 



797 



Kino, 114 

Kips and skins, handling with Gor- 
sline's apparatus, 357 
the skins of small or yearling cat- 
tle, 38 
Kirkaldy, David, experiments of, with 

chrome leather, 62 
Kirkaldy's experiments with chrome 

leather and tanned leather, 639 
Klemni, tawing process invented by, 

689 
Klemm's leather, tests of, with boiling 
water, 695 
oil leather, coloring, 694 

preparation of, 693-697 
strength of, 694 
process for making oil leather, 
character of, 693 
for oil leather, advantages of, 

694 
Prof. Fehling on, 695 
tanning process for oil leather, 
693-697 
Knapp on the complete saturation of 
the skin tissue by alum, 132 
on the experiments of Ludwig 
Kester on the quantities of tan- 
nin of various kinds absorbed by 
skins, 126 
Knapp's attempts to reintroduce tan- 
ning with ferric salts, 135 
experiments in obtaining leather 
solely with fatty substances, 
364, 365 
in I'egard to "I'otten," or 
"burned" leather, 677, 
678 
in regard to tanning and taw- 
ing, 660 
fulling drum for tanning, 630-632 
iron soap, 135 

in tanning, 630 
latest process of mineral tanning, 

633 
mineral tanned leather, charac- 
teristics of, 632, 633 
process for tanning with ferric 
salts and other metallic ox- 
ides, 628 
mineral constituents in leather 

tanned by, 8t 
of tanning 1877, new and 
peculiar features and ad- 
vantages claimed for, 632 
of tanning with ferric salts, 
1877, 629-633 



Knapp's process — 

of tanning with salt solutions 
and soap baths, 695- 
697 
with stearine in spirit of 
wine, 697 
processesfor mineral tanning, 1861 
and 1877, 628, 629-633 
Knife, unhairing, 304-306 
Knives, curriers', 423, 424 

patents for, 430 
Knox's finishing and pebbling machine 
lor glassing and 
rolling brushed 
kid, 532 
for Morocco, 464, 
465 
Kohler on determination of tannic acid, 

144 
Koppitz and Mayer's process of color- 
ing leather on starch surface, with 
an appearance similar to marble 
paper, 768, 769 
Krameria triandra, 121 



LAB AN AND JACOB, early herds- 
men, 34 
Lace and whip leather, quick tanning 
process for, 567 
leather, 563, 572 

Junior's method of manufac- 
turing, 565-567 
Loescher's method for manu- 
facturing, 567', 568 
Lactantius on the reindeer clothing of 

the German tribes, 37 
Lactic acid, 112 

Lamb- and kid-skins, assorting, 644 
prices and (qualities of, 
644 
and sheep, diseases of, effects of, 
on leather, 674, 675 
Lamb-skins, Aikens's method of work- 
ing into glove leather, 664- 
667 
for glove .leather, 643, 644 
of Asia Minor, France, and 

Italy, 42 
treatment of, and uses, 41, 42 
Watts' s method of makins 
into glove leather, 666 
Lampblack, 69 
Lampert's machine for workin<>" hides, 

338-341 
Larch bark, 118 



798 



INDEX. 



Larix Eurojicea, 118 

Larrabee's unhairing machine, 314- 

318 
Laure's process of depilating with 

water in an open vessel, 286, 287 
Lay-away vats for sole leather, 365 

the liquor in, 367 
Layers, number of, and period for each 

in laying-away, 366 
Laying-away, 363-368 

for finer grades of leather, 

366, 367 
green stock, 366 
practical details, 365-368 
Leach, regulating the volume of water 
or liquor run to the, 220 
round, to find the capacity of, 212 
the sprinkler, 203, 204 
Leaches, conductors to the, 218, 219 
false bottoms for, 211 
filling ami running the, 219-226 
flooring about the, 212 
form of a supply tank for, 214 
round, building,' 209-219 
steady pressure for, to secure, 213 
table showing the capacity of, 213 
the kinds of, employed, 203-209 
the size and capacity of, 224 
Leaching and making extracts from 
tan-bark, patents for, 235, 236 
apparatus, Johnson's, 204-208 
finishing, 221 

fluid, a liquor denser than water, 
inferior, 221 
distribution of the, 220 
old or weak liquors as a, 222 
water as a, 221 
of bark, importance of, 184 
tan-bark, 203-236 
the best method of, 203 
the use of heat in, 221, 222 
with little or no heat, 223 
Lead chromate, 718, 719 
nitrate, 714 
sugar of, 716 
Leather, a la garouille, 127, 129 
alligator, "582-585 
alum, 69 

alumed, defects of, 673, 679 
aluminium chloride used for in- 
creasing the weight of, 86 
American, high rank of, 78 
artificial, 72 

tannins used for tanning, 137 
ash in determination of the per- 
centage of, 82 



Leather — 

average consumption of, among 
the populations of Europe much 
less than In the United States, 
73 
barium chloride used for increas- 
ing the weight of, 86 
bark-tanned, effect of steeping in 

water, 62 
behavior of, towards boiling water 
when not thoroughly tanned, 
85 
brought from Asia into Euro])e at 

an early day, 65 
brown, for skivers, 749 

light, 729 
buff, 69 

calf, ability of, to resist water, 88 
carpets used in the time of Moses, 

56, 57 
chamois, 64 
change in volume and ability of 

resisting water, 87-89 
chemically considered, 63, 64 
chestnut bark tanned, 127-129 
chrome, effect of boiling in water, 
62 
effect of steejsing in cold 

water, 62 
the effect of stuffing with fat 
or paraffine, 62 
colored, antiquity of, 65 

spoken of by Ezekiel, 56, 57 
various places in which it has 
been manufactured, 66 
coloring matter in a tannic acid 
may injure the appearance 
of, 113 
with mineral pigments, 735, 
736 
commercial varieties of, 63, 64 
Cordovan, 65, 66 
currying establishments in tiie 

United States, 79 
determination of means used to 

increase the weight of, 86 
determination of the value and 

quality of, 81 
dressing machine, Fitzhenry's, 

398-401 
dyeing, 698-758 
enamelled, 69 
evening or making of uniform 

thickness, patents for, 551 
exjx'riments of Miintz and Schcin 
on the real value of, 127-129 



INDEX. 



799 



Leather — 

exports and imports of, 7 7 

extractive substances to the ex 
tent of 23 per cent, removed 
from hemlock-tanned, 127 

fat and resin in, determination of, 
81, 82 _ 
in determination of, 83 

French or Erlanger, 642 

fir-bark tanned, 12 7-129 

Huffing and grounding machines, 
patents for, 550 

for carriage tops, 70 

for glovers and harness-makers' 
use, 64 

foreign, the most famous, 65 

free from resin, pounds of, ob- 
tained from 220 pounds of dry 
skin with different tanning ma- 
terials, 129 

from alligator skins, qualities, 
uses, and where made, 44 

from dog-skins, 43 

from elephant-hides, 43 

from hippopotamus-hides, 43 

from hog-skins, 43 

from horse-hides, 43 

grape sugar used for increasing 
the weight of, 86 

percentage of glue in, 128 

hemlock, 127-129 

hemlock and fir-bark give the best 
weight in tanning, 127 

hemlock-bark tans two-thirds of 
American productions of, 118 

horse-chestnut and oak-barks 
mixed for tanning, 120 

Hungarian, 64 

increase in the weight of skins by 
conversion into, 126, 127 

increasing the weight of, determi- 
nation of the means used, 86 

industry of the United States, ex- 
tent and importance of, 73 

influence on, of tannic acid yield- 
ing pyrogallic acid, 113 

its characteristic properties, 63 

Japanned, 70 

Kangaroo, 583 

Knapp's method of employing 
ferric salts for tanning, 
135 
mineral tanned, characteris- 
tics of, 632, 633 

lace, 563, 572 

lime in, determination of, 82 



Leather — 

liming too long gives poor weight 
and impairs the strength of, 
_ 98 
list of the names applied to, in 

commerce, 71, 72 
measuring machine of Williams, 
Moore, and Hurlburt, 
469-473 
Sawyer, 473-479 
mineral constituents in, determi- 
nation of, 85 
of, when tanned by 
Heinzerling's method, 
85 
of, when tanned by 
Knapp's method, 85 
tanned, ability of, to resist 
water, 87-89 
Mittenzweig's method of deter- 
mining the tannic acid in, 85 
Mogador, 70 
Morocco, 65, 66 

produced at Mogador, 70 
nitrogen in, determination of, 84 

in, percentage of, 128 
Norwegian glove, 119 
not a chemical compound, 63 
oak-bark tanned, 127, 128, 129 
obtained by Knapp without tan- 
nin elements, 364, 365 
oil, 70 

parchment, 68 

pathological and physiological 
tannic acids, influence exerted 
in the production of, 102 
prepared with sumach, qualities 

of, 117 
probably not a chemical combi- 
nation, 364 
produced by the aid of picric 

acid, 138 
quality of dependent upon the 
thickness, flexibility, and 
strength of the corium, 94 
of, not improved by remain- 
ing a long time in the vats, 
129 
quebracho, 127, 128, 129 

and chestnut bark used for 

tanning, 125 
claimed to produce good, 122 
raw materials employed in the 

production of, 93 
resin and fat in, determination of, 
81, 82 



800 



INDEX. 



Leather — 

resins may injure the (juality of, 

113 
resistance of, to breaking, 89 

of, to tearing, 89 
roan, 70 

rock chestnut oak a valuable 
material in the United States 
for tanning, 119 
russet, 70 
Russia, 574-582 

decadence of the use of, for 
bookbinding. 67 
- saffian, 70 

scourer and setting machine, 

Lockwood, S86-;>92 
scouring machines, Deheney table 

for, 405-407 
scraps and waste, process for 
making artificial leather im- 
pervious to moistui'e, 489, 490 
shagreen, G5, 67 
sides of, shown hung over poles in 

the drying-yards, 496 
skin or corium, 93, 94 
skiver, 70 
soft for gloves, 642 
sole, 481-491 

ability of, to resist water. 88, 
89 
split, 70 
splitting, 368-384 

machine, McDonald and 
Beggs, 375-378 
strength of, decreased by long 
liming, 98 
of, in various parts of the 
skin, 91, 92 
sumach-tanned, 64, 128 ^ 

generally used for tanning 
Morocco, 125 
tan, ability of, to resist water, 88, 

89 
tanned, classed as hides, kips, and 
skins, 38 
with chestnut bark and que- 
bracho, advantages claimed 
for, 129 
with divi-divi, qualities of, 1 1 7 
with oak bark after being- 
washed with ether and 
alcohol, 129 
tannic acid in, determination of, 
85 
yielding pyrocatechin, 
influence of on, 113 



Leather — 

tannin absorbed by each one 
pound of skin in the pro- 
duction of, 125-129 
in, percentage of, 128 
tanning substances in, determi- 
nation, 85 
testing the strength of, 89-92 
the art of varnishing, 59 
"to draw from" the significa- 
tion of the old expressions, 
58 
to render the fibre more absorbent 
of chemical compounds and 
dyes, 552, 553 
twisted, 689 
used at an early date bj' the 

Israelites to write upon, 56 
used by the Greeks in the con- 
struction of ships, 57 
varieties of, tanned with sumach, 

116 
vegetable, 72 
walnut bark produces a soft 

variety of, 119 
wash, 71 

water in, determination of, 82 
weight of, decreased by long lim- 
ing, 98 
Weiner's device for testing the 

strength of, 89 
whang, 71 
white, 71 

whitening and buffing machine, 
428, 429 
machine, Clements's, 424- 
428 
willow bark used for tanning 
Russia, 121 
used for tanning Swed- 
ish glove, 121 
Leatherette, 581 

Leathers, assorting for dyeing, 726- 
728 
examination of, 81-92 
tanned with tan-bark and with the 
gall-nut, comparative behavior, 
365 
Lee's patent, artificial tannino; material 

of, 137 
Lemon color, 733 

Liebig on the action of potash on tan- 
nin, 107 
on the transformation of tannin 
into gallic acid, 106 
Light brown, 733 



INDEX. 



801 



Light brown — 

and darker colors on leather 
with oxalic acid, salt of tin, 
etc., 767, 768 
leather-brown, 729 
leathers sold by measure, 468 
not a simple body, 698 
olive-green, 733 
what it results from, 698 
Lilac, 724 

Lime and orpiment as a depilatory, 
275 
and sulphur action of in depilat- 
ing, 283 
blood, and water for depilating, 

284-286 
gas as a depilatorj'-, 27,') 
hydrosulphate of, depilation with, 
288 
of, preparation of, 288-290 
inconveniences of using for depi- 
lating, 2G 1-263 
in leather, determination of, 82 
liquor and sulphuric acid for bat- 
ing, 344 
necessary for a vat, 265 
orpiment and potash as a depila- 
tory, 288 
pits, 264 

use of, with upper leather, 492 
vats, construction of, 265 
in Morocco factory, 525 
"live" and "dead," 266 
series of, 266 
water, 710 

and suljihurous acid as a de- 
pilatory, 278 
Limes, 710, 711 

how long the goat-skins, glove 
calf, and glove sheep, remain 
in, 526 
the practice of the use of old, 

hazardous, 266 
treating the hides in the, 2G4-266 
Liming and depilating for glove 
leather, 648, 649 
duration of, 266 
for chamois leather, 681 
hides. Study's contrivance for, 
357 
too long gives poor weight, 
98 
process, 261-269 
Linings, artificial sheep-skins for, 561, 

563 
Linseed oil, boiled, 69 
51 



Lippowitz on precipitation in deter- 
mining tannic acid, 143 
Liquid for curing hides, composed of 
pyroligneous acid, aloes, and alum, 
52, 53 
Liquors, concentrating, 222 

going into the leaches to be 
strained, 213, 214 
in the lay-away vat, 367 
List of compounds and materials for 
tanning and for tawing leather 
and for preparing raw hides, 
especially claimed or mentioned 
in any patent, 616-619 
of patents for apparatuses for 
blacking leather, 449 
for apparatus for stretching 

leathers, 596 
for bark mills, 195-197 
for bark-rossing machines, 

182 
for blacking compounds for 

leather, 451-453 
for breaking hides, 261 
for compounds for bating 
hides and skins, 351 
for cm-rying leather, 420 
for depilating hides and 

skins, 302, 303 
for polishing and color- 
ing leather, 775 
for stuffing leather, 420 
for curriers' knives, 430 

slickers, 430 
for employing mineral sub- 
stances for tawing hides and 
skins, 641 
for hide mills, 260 
for leather splitting machines, 

383, 384 
for machines for boarding and 
graining leather, 439, 
440 
for evening or making 
leather of uniform 
thickness, 551 
for measuring the areas 
of hides, skins, and 
leather, 480 
for pebbling leather, 467 
for removing grease from 

leather, 422 
for rolling leather, 467, 

468 
for sharpening curriers' 
knives, 430 



802 



INDEX. 



List of patents for machines — 

for stoning, polishing, 
finishing, glassing, 
glazing, tlinting, 

creasing, and dicing 
leather, 465-467 
for whitening, buffing, 
and shaving leather, 
430 
for methods and machines for 
packing tan-bark for 
transportation, 183 
for manufacturing enam- 
elled, japanned, and 
patent leathers, 595, 
596 
for preserving hides, 54 
for processes and apparatuses 
for leaching and mak- 
ing extracts from tan- 
bark, 235, 236 
employing apparatus for 
tanning leather, 614- 
616 
for tanning leather, 609- 
614 
for putting out machines and 
leather tiuffing and ground- 
ing machines, 550 
for scouring and setting 

machines, 407, 408 
for softening hides, 246 
for tanners' vats, agitators, 
and handling appliances, 
358, 359 
for unhairing and fleshing 
machine, 333-335 
Litmus paper, its use for detecting 
fraudulent increase in the weight of 
hides, 49 
Live oak, 122 
Lixiviation, how commonly conducted, 

203 
Lockwood, automatic leather scourer 
and setting machine, 386-392 
designs of, in his later scourer and 
setting machine, 391, 392 
Loescher's metliod for manufacturing 

lace leather, 567, 568 
Loft of a Morocco i'actory, showing 

the skins spread on the floor, 532 
Logwood, 118 

solution, saturation of leather 
with, 553 
Lombardy poplar bark, 119 
Loom and the distaff, early use of, 36 



Lot and Abraham, rich in cattle, sil- 
ver, and gold, 34 
Lowenthal's method of determining 
tannic acid, modified by Neu- 
bauer, 154-163 
mode of determining the tannic 
acids in bark, 163 
Lucas aniline black, 745 
Luray, Virginia, details of the process 
of manufacturing oak slaughter 
leather at, 483-486 
Lustre, giving leather, after dyeing, 725 
on dyed oil leather, 738 
on harness leather dyed with ani- 
line colors, 758 
Lye from wood ashes or potash and 
lime, which has been treated by the 
gas generated by sulphuric acid, 
sulphuret of iron and water for 
unhairing hides and skins and jell- 
ing wool, 278-281 
J^ynds's depilatory, 276 
Lynn, Mass., large quantities of Mo- 
rocco produced in, 66 



MAcBRIDE, DR., 58 
discovery of 1774 in regard to 
hydrochloric acid, 336 
the discovery of the use of sul- 
phuric acid for plumping, b}', 
597 
MacBride's discovery of plumping by 
means of sulphuric acid, 
361-363 
of the process of raising with 
diluted sulphuric acid, 5S 
McDonald and Begg's leather sj^litting 

machine, 375-378 
McDonald's improvement in feed 
rolls for unhairing machines, 
325-327 
unhairing machines, 322-327 
McKenzie's evaporator, 230 
McMurtrie's compound, 346 
Machine belt leather greased with tal- 
low, 522, 523 
belts, crown leather for, 692 
for removing grease from leather, 

421, 422 
for smutting leather, Bryant's, 
447-449 
Machinery in tanning processes, the 

general introduction of, 493 
Machines ibr boarding and graining 
leather, patents for, 439, 440 



INDEX, 



803 



Machines — 

for evening or making leather of 
uniform thickness, patents for, 
551 
for glassing or polishing, peb- 
bling, finishing, rolling leather, 
etc., 453-468" 
for measuring leather, 468-480 
the area of hides, skins, and 
leather, patents for, 480 
for rolling leather, patents for, 

467, 468 
for stoning, polishing, finishing, 
glassing, glazing, Hinting, creas- 
ing, and dicing leather, 465-467 
for wliitening, bufhng, and shav- 
ing leather, patents for, 430 
Madder red upon oil leathers, 737, 738 
Magenta, 743, 744 
Maine, tanning interest in, 75, 76 

the bark obtained from, 494 
Main's process of finisliing alumed 

leather, 667, 668 
Malabar or East Indian kino, 114 
Malpighi's net, 94, 95 
Mammalia, skins of the, 36 
Mammiferous animals, uses of, to man, 

39 
Mamre, the plain of, 35 
Manasse's method for tawing sheep- 
skins, 558, 559 
Manganese, 53 
alum, 132 

dioxide in tanning, 627 
peroxide of, 107 
Manganous sulphate, 131 
Marine salt, 108 

Maroon, black, and purple colors, im- 
parting to raw hides, 759, 760 
Manjuis's method of examination of 

leather, 81 
Martin's machine for glassing and 

finishincf leather, 454-458 
Martin's yellow, 747 

yellow on Morocco, 757 
Martyn's black compound for leather, 
758 
composition for polishing, water- 
proofing, and coloring leather, 
771, 77^2 
Mason's building for sweating hides and 

skins, 293-295 
Massachusetts, bark bought by the cord 
in, 494 
currying business in, 79 
tanning interest in, 75, 76 



Materials and compounds for tanning 
and tawing leather, and lor prepar- 
ing raw hides, especially claimed or 
mentioned in any patent, 616-619 
Mats made from sheep-skins tanned 

with the wool on, 42 
Mauve, 743 

Maynard's bating process, 346-349 
depilatory of lime-water and sul- 
phurous acid, 278 
May's compound for changing the 

color of leather, 773, 774 
Means used to increase the weight of 

leather, determination of, 86 
Measure, the, for a leather dyer what 
scales and weights are for the 
chemist, 702 
Measuring leather, machines for, 468- 
480 
machine for leather. Winter's, 
468, 469 
of Williams, Moore, and 

Hurlburt, 469-473 
Sawyer, 475-479 
Winter's, 468, 469 
machines invented in the United 

States, 468 
the areas of hides, skins, and 
leather, 480 
Mechanical work of dyeing alumed 
leather, and directions for preparing 
and applying vegetable dyes, 72]- 
732 
Merrill & Hoitt's process for prepar- 
ing raw hides, and imparting black, 
maroon, and purple, colors to them, 
759-761 
Merrill's process for boarding jDatent 

leather, 592 
Merritt's process for producing 
japanned leather in imitation of 
alligator skin, 594, 595 
Mesquite oak, 122 
Metagallic acid, 1|)5, 106 
Metallic oxides in tanning, 627 

salts for preparing leather for mar- 
ket, 552 
soap, 53 

Knapp's process of tanning 
with, 628 
Methods for determining the constitu- 
ents of water, 169-173 
Methyl, alcohol, 53 

green on Morocco, 756 
violets on Morocco, 757 
Methylene blue O, for skivers, 748 



804 



INDEX. 



Mexico, goat-skins of, 42, 43 
Middleton's hide-mill, 258-260 
Mi-fonce brown, 730 
Mill for softening hides and for fulling 
cloth, described and illustrated, 
256-258 
Mills, hide, 250-260 
Mimosa, 122 

■where used for tanning, 125 
Mineral acids, depilating with, 265 
and artificially prepared tanning 

substances, 130-138 
constituents of leather, determi- 
nation of, 85, 86 
kingdom, 35 
pigment, 735, 736 
substances for tawing hides and 

skins, patents for, 641 
tan, Lee's, 137 

tanned leather by Knapp's pro- 
cess, characteristics of, 
632, 633 
Heinzerling's, ability for 
resisting -water, 87- 
89 
tanning, 626-641 

chromium alum the most 
important salt used in, 134 
materials, 130-136 
processes which have been 

abandoned, 629 
•what is understood by, 626 
Mittenzwei and Terriel's method of 

determining tannic acid, 147-150 
Mixed brown, 734 
Modified color, 701 
Mogador leather, 70 
Mohr's process for exhausting gall- 
nuts, 104 
Molac and Triedel's process for tan- 
ning with ferric salts, 627 
Monier, use of potassium ferrocyanide 
solution for precipitating tannic acid, 
154 
Montevideo, quality of the hides from, 

40 
Mordant for glazed leather, 726 

used in Russia in dyeing Russia 
leather, 576, 578 
Mordanting leathers for aniline colors, 
740, 741 
Russia leather, 577, 578 
Mordants, 705-721 

what they are, 705 
when necessary with aniline colors, 
740 



Moret's composition for impregnating 
hides and skins, and preserving them 
in condition to be unhaired by im- 
mersion in water, 50-52 
Morintannic acid, 101 
Morocco and Russia leathers, dyeing 
with aniline colors, 754-758 
boarding and graining, machine 

for, 4'38, 439 
factory, drying loft of a, showing 
the skins hung up, 530 
lime vats in a, 525 
loft of a, showing the skins 

spread on the iioor, 532 
view in a, 525 

view of the tan tubs in a, 527 
finishing and pebbling machine, 

Knox's, 464, 465 
glazing machines,* 462-465 
hand method of tanning, 541, 542 
leather, 65, 66 

classification of, 524 
compounds for producing, 

551-555 
produced at Mogador, 70 
sumach genei'ally used for 

tanning, 1 25 
superseding Russia leather 
for bookbinding in j)ublic 
libraries, 67, 68 
uses of, 524 

what is understood by, 524 
leathers, 524-555 

the skins from which they are 
produced, 524 
manufacture, decline of, in Russia, 
66 
in the United States, 66 
manufacturers, AValters's fulling 

cup for, 539-541 
process for finishing lower grades 

similar to, 552-555 
putting-out machines for, 545-551 
tannery, skins removed from the 

lime vats, 525 
tanning in a combined wheel and 
"vat, 542-545 
preparing the skins for, 525- 
527 
ware, water- proof, 535 
]\loru!> tinctoria, 118 
Mosser's safety coupling for bark mill, 

186-188 
Mother liquors for glazed leather, 729 
Moths, destruction of, 645, 646 

injury of skins by, 645-647, 675 



INDEX. 



805 



Mower's depilatory process, 278-281 
Mullen's bating process, 349 
Munfez and Rampercher's apparatus 
for filtering tanning licjuor foi- 
the purpose of determining tan- 
nic acid, 140 
and Sclion, experiments of, re- 
garding the absorption of 
different tannins by the 
skin, 127, 128 
on leather tanned with oak 
bark after being washed 
with ether and alcohol, 129 
on tanning with quebracho, 
122 
and Schon's opinion that leather 
is a solid combination, 
127 
that the percentage of 
tannin in pure leather 
is a test of the quality 
of the leather, 127 
on the determination of nitrogen 
in leather, 84 
Muriate of ammonia, 336 

bating with, 341, 343 
of soda, super-tartrate of potassa, 
and tartaric acid as a bating 
compound, 342, 343 
Muriatic acid and burnt oolite, 284 
Myrobalan used in Europe as an 
addition to oak bark in tanning, 
118 
Myrobalans, 117, 118 



NAMES applied to leather in com- 
merce, list of, 71, 7 2 

Nankeen browns for skivers, 754 

Nankin color, 724 
yellow, 734 

Naphthaline colors, 747 

Naphtharazine, 747 

Naphthol yellow L for skivers, 749 

Naphtyl blue, 747 

Naphthylamine red, 747 
violet, 744 

Napier's process for preserving hides 
and skins, 53 

Nature, empire of, divided into three 
kingdoms, 35 

Neubauer on Wagner's method of de- 
termining tannic acid, 53 

Neubauer's modification of Lowen- 
thal's method of determining tannic 
acid, 154-1G3 



Neubauer's — 

treatment of a sample of oak bark, 
160, 161 
Neutral alkaline chromates, 134 
Newark, N. J., manufacture of enam- 
elled leather in, 70 
Morocco industry in, 66 
production of Russia leather 
in, 6 7 
New Jersey, tanning interest in, 75, 76 
New York, tanning interest in, 75, 76 
Nitrate, 714 

of potassa in soaking hides and 

skins, 239 
of silver as a test for chloride, 86 
Nitric acid, 107, 707 

decomposition of, 707 
its use for acidulating in test- 
ing for barium salt, 86 
its use in determining the 
percentage of lime In 
leather, 83 
use of, in preparing artificial 
tannin, 136, 137 
Nltroo-en in leather, determination of, 
"84, 85 

percentage of, in leather, 1 28 
Noble's tanning process, 601, 602 
Norwegian glove leather, elm bark in 
the manufacture of, 119 







AK AND HEMLOCK BARKS, 

general use of, in the 

United States, 598 

the astringent principle 

of, the same, 481, 482 

bark and myrobalan used together 

in Europe for tanning, 118 

chemical examination of, 1 59- 

163 
consumed in tanning in the 

United States, 75 
substances In the inside layer 

of, 139 
to obtain a correct sample of, 

for analysis, 160 
where used for tanning, 125 
barks, 119 

slaughter leather, made at Luray, 
Virginia, 483-486 
varieties of, 482 
sole leather tanning and finish- 
ing, 483-486 
tanned leather generally of the 
choice hides, 481 



806 



index: 



Oak— 

taiuied sole leather, reasons for 
commanding a higher price, 
481 
Texas hide leather, varieties of, 

4S2 
wood, tannin obtainedfrom, 122 
Oaks of different ages, tannic acid 

yielded by, 112, 113 
Obsolete depilatory methods, 300- 

302 
Ochre, 69 

Oil, fiiUing chamois leather in, 682- 
68 S"" 
goat finishing, 535 
leather, 70 

colored black for shoemaker's 

purposes, 689 
Klemm's preparation of, 693- 

697 
to restore softness to dyed, 739 
of vitriol, 706 
of vitriol, salt, and bran, bating 

with, 344, 340 ' 
or chamois leather, dyed by dip- 
ping, 736 
dyeing with aniline co- 
lors, 741 
manufacture of, 679-689 
uses of, 679 
Olive, 730 

brown, 733 
green, 724 
greens, 733 
oil for tanning, 655 
Oliver and Howell's machine for 

stretching leather, 588, 589 
Oolite and muriatic acid for depilating, 

284 
Orange, 734 

B R for skivers, 751 
fat color on straps, 758 
on Morocco, 756 

tones or the redder shade on Mo- 
rocco, 757 
Orceine B for skivers, 750, 751 
Organic acid for bating, 336 
Oriental ancient tanning, 65 
Ornamenting and gilding leather for 

suspender ends, 765 
Orpiment, lime, and potash, as a de- 
pilatory, 288 
Osmic acid, 107 
Osmium, oxide of, 107 
Overhead ijlazing machine for Mo- 
rocco, 4 64 



Ox, the uses of, to man, 39 
Oxalic acid, 82, 107, 708 

preparation of solution of, 
155 
Oxides in tanning, metallic, 627 
Oxychloride of phosphorus, 108 



PACKING tan-bark for transporta- 
tion, methods and machines for, 
183 
Page's tanning process, 602 
Painting, dyeing by, 724-732 
Pallas, the traveller on the production 

of shagreen leather, 67 
Pangue, 122 
Parchment, artificial, 68, 69 

dyeing with aniline colors, 741 
history, uses, and principal places 

of production, 68, 69 
the purposes for which it is used, 

69 
vii-gin, 68 

whence the name is derived, 68 
Parenchjma in bark, 175 
Parisian violet, 741 
Parkins' s bating compound, 343, 344 
Part cured hides, 55 
Pastes, tawing for olove leather, 653- 

661 " " 

Patent enamelledand japanned leather, 
patents for, 595, 596 
japanned or enamelled leather, 

585-596 
leather, boarding, 592 

degrees of heat for drying, 

590 
drying, 590 
ground laying mixture for, 

590 
hides used for, 583 
pumicing the surface of, 591 
substitute for, 595 
tanning material used for 
hides, intended for, 585, 
586 
treatment of the hides for, 

580-592 
varnish for, 592 
A^arnishing, 592 
system of the United States, 54 
Patents, compounds, and materials for 
tanning and tawing leather, and for 
preparing raw hides, especially 
claimed or aientioned in any, 616- 
619 



INDEX. 



807 



Patents — 

for apparatuses for blacking 
leather, 449 
for stretching leather, 596 
for bark-rossing machines, 182 
for bark mills,^195-197 
for blacking compounds for lea- 
ther, 451-453 
for compounds for bating hides 
and skins, 357 
for coloring and polishing 

leather, 7 75 
for currying leather, 420 
for depilating hides and skins, 

302, 303 
for stuffing leather, 420 
for curi-iers' knives, 430 

slickers, 430 
for employing mineral substances 
for tawing hides and skins, 641 
for leather splitting machines, 383, 

384 
for machines for boarding and 
graining leather, 439, 
440 
for evening or making leather 
of uniform thickness, 557 
for measuring the areas of 
hides, skins, and leather, 
480 
for pebbling leather, 467 
for rolling leather, 467, 

468 
for sharpening curriers' 

knives, 430 
for stoning, polishing, 
finishing, glassing, glaz- 
ing, flinting, creasing, 
and dicing leather, 465- 
467 
for whitening, buffing, and 
shaving leather, 430 
for methods and machines for 
packing tan bark for trans- 
portation, 183 
for manufacturing enamelled, 
japanned, and patent 
leathers, 595, 596 
for preserving hides, list of, 54 
for processes and apparatuses for 
leaching and making ex- 
tracts from tan-bark, 235, 
236 
employing apparatuses for 

tanning leather, 614-616 
for tanning leather, 609-614 



Patents — 

for putting out machines and 
leather fluffing and grounding 
machines, 550 
for scouring and setting machines, 

407, 408' 
for tanners' vats, agitators, and 

handling appliances, 358, 359 
for unhairing and fleshing ma- 
chines, 333-335 I 
Pathological tannic acids, 102 
Patterson's process for forming an 
artificial grain on the hide after it 
has been buffed or split by a 
machine, 593, 594 
Payen's experiments in the distillation 

of birch oil, 580 
Peabody, Mass., the upper leather 

pi-oduced in, 493 
Peach color, 724 
Pearl ash, 718 
Peat, tannin from, 138 
Pebble and grain leathers, handling 
the sides for, 357 
grain goat finishing, 535 
Pebbling and finishing machine, 
Knox's, 464, 465 
leather, patents for machines for, 

467 
polishing, glassing, finishing, roll- 
ing leather, etc., machines for, 
453-468 
Pectic acid, 113 

exerts no influence upon a so- 
lution of potassium manga- 
nate, 162 
Pectine, 113 

Peeling the bark, and the most con- 
venient time for doing it, 176, 1 77 
Pelouze's process for the extraction of 

gallotannic acid, 103 
Peltries, processes for softening, 243- 

246 
Pennsylvania, bark from, 494 
taiming interest in, 75, 7 6 
Perkins's machine for removing grease 
from leather, 420, 421 
violet, 741 
Permanganate of potash solutions, re- 
duced by tannin, 107 
Persoz's method of analyzing tanning 
materials, 141, 142 
process for coloring black with 
aniline, 745 
Peschir, on the tannin of ratanhy root, 
121 



808 



INDEX. 



Pfanhanser's process for tanning with 

a basic ferric sulphate, 628 
Phenol brown, 747, 748 
colors, 746 
red, 746 
Philadelphia, Pa., importiance of the 
raoroeco industry in, 66 
production of Russia leather 
in, 67 
Phillips's process of bleaching hemlock 
tanned and union tanned leather, 
488, 489 
Phloroglucin, 112 
Phoenicians, leather ships of, 57 
Phosphine-orange on morocco, 755, 

757 
Phosphoric acid, 105 

for bating, 336 
of glue factories, for bating, 
349 
Phosphorus, oxychloride of, 108 
Phyllocitannic acid, 120 
Physical means to test leather, 86-92 
Physics, 714 

Physiological tannic acids, 102 
Pickard's tanning process, 605 
Pickhardt & Kuttroff, aniline colors 

of, 748 
Picnometer, 144 

Picric acid, formula of, and mode of 
production, 138 
skin conA'erted into leather, 
by, 138 
green, 733 
Pimicia granatum, 122 
Pingree's process for tanning hides with 

the hair on, 620 
" Pin mill" for Morocco tanning, 525 
Pinu.t abies, 118 

halepensis, 12,1 
Platinum chlorine, 84 
Platoso-ammonium chloride, 84 
Plumbic acetate, 7 1 6 
Plumer and Kernan's process for re- 
moving extractive matter from 
tanned leather, 503, 504 
Plumping and depilating hides and 
skins, 282, 283 
applied only to the heavier 

classes of hides, 360 
by means of sulphuric acid, 361- 

363 
hides, MacBride's discovery of the 

use of sulphuric acid for, 58 
or swelling, 359-363 
the essential action of, 359 



Plumping — 

two processes of, 360 
with sulphuric acid, precautions 
to be taken in, 362 
Polish for leather, used for bags, 
satchels, etc., 772, 773 
to leather, a base for, 771 
Polishing and coloring leather, com- 
pounds for, 755- 
775 
patents for, 775 
glassing, pebbling, finishing, roll- 
ino; leather, etc., machines for, 
4.53-468 
glove leather, 661-663 

with tlat-irons, 663 
machines, patents for, 465-467 
water-prooiing, and coloring 
leather, composition for, 7 71, 
7 72 
Pollock's process of making artificial 

sole leather, 489-491 
Porpoise skin, 44 
Potash, 717, 718 
acetate of, 105 
alum, 131, 713 

principally used in tawing 
and in mineral tanning, 132 
American, 51 
bichromate of, 107 
lye, its use in determining the per- 
centage of fat in leather, 83 
lime and orpiment as a depilatory, 
288 
Potassa, 70 
Potassium bichromate, 133, 718 

characteristics and qualities 

of, 133, 134 
for tanning, 628, 629 
withdrawn from different 
samples of chrome-tanned 
leather by the action of 
water, 636-640 
bi tartrate, 717 
carbonate, 717, 718 
chloride of, 61, 62 
ferriccyanide, 719, 720 
ferrocyanide, 719 
hydrate, 709, 710 
manganate, solution of, prepara- 
tion of, 155 
Preller's H B crown leather, 691- 
693 
leathej', weight of, 691 
method, manufacture of horse 
leather by, 693 



INDEX. 



809 



Prellev's method — 

of tawino;, 689-693 

time required for, 692 
process, why it hns not been more 
generally adopted, 693 
Preparation of the hides for heavy 

iippei- leather, 494, 495 
Preparing, coloring, and polishing 
light skins for car seats, trunk 
covers, etc., 770 
tan-bark for use, 197-200 
the cut surface of split leather for 
manufacturing japanned or 
enamelled leather, 592-594 
Preserving hides, 49-55 

hides and skins, Moret's compo- 
sition for, 50-52 
Napier's -process for, 53 
Sabathe and Jourdan's 
process for preserving, 
53 
Wickersheimer's pro- 
cess, 53, 54 
list of patents for, 54 
Rock's process, 52 
Primary colors, modifications which 
these colors are capable of under- 
going, 700 
Primicive colors, 699 
Prism, the, 698, 699 
Principles and facts in the sciences and 

arts, 56 
Process for finishing lower grades of 
leather, similar to Morocco, 
552-555 
for plumping before depilating, 
and the treatment of hides or 
skins, with an acid solution 
before liming for the removal of 
salt or other matter, 246-250 
for preparing tan-bark for use, 

197-200 
for preserving hides and skins, 

Sacc's, 53 
and compounds for depilating hides 
and skins, 261-303 
Processes employing apparatus for 
tanning leather, patents for, 
614-616 
for softening hides, skins, and 

peltries, 243-246 
for tanning leather, patents for, 

609-614 
for water- proofing, dubbing, and 
whitening upper leather, 504- 
507 



Proctor's upper leather tannery, a 

view of the cellar of, 368, 369 
Proprionic acid, 112 
Protacete barks, 121 

the tannins of, 121 
Protea conocarpa, 121 
Protocatechuc acid, 112, 120 
Proust, 58 

Prussiate of potash, yellow, 719 
Fterocai'pus, erinaceus, and mar- 

snpium, 114 
Pultz's process of aluminium tannino-, 

641 
Pumicing the surface of patent leather, 

591 
Purifying extracts of bark, 227-231 
Purple, black, and maroon colors im- 
parting to raw hides, 759, 760 
Putnam's composition for finishing 

split leather, 451 
Putrid soaking, 312 
Putting out goat- and sheep-skins, 545 
machine, 545, 546 
machine, Hoffman, 545-550 
machines for Morocco, 545- 

551 
machines, patents for, 550 
Pyrocatechi n ,113 
Pyrogallic acid, 105, 113 

glucoside, 109 
Pyroligneous acid, 52, 708 



QUALITATIVE examinations of 
water, 169 
Quebracho, 122 

and chestnut bark, tanning with, 
129 
used for tanning in 
England, etc., 125 
where used in tanning, 125 
Qu ere i tannic acid, 101 
Quercitron yellow, 734 
Quercotannic acid, cpuilities, compo- 
sition, and formula of, 110, 111 
Quercus ac/ilops, 117 

bitter or quercin, 111 
infectoria, 115 
vioniicnUi, 119 
pedunculta, 115 
red. 111, 112 
tinctoria, 119 
tirens, 122 
Querphlobaphene, 112 
Quick tanning process for lace and 
whip leather, 567 



810 



INDEX. 



Quick tanning — 

Seguin's system of, 58 
Q.uinland's compound for imparting a 

lustrous black gloss to leather, 764 
Quinotannic acid, 101 



RABE on the formula of the tannin 
in ratanhy root, 121,122 
Rady's process for water-proofing, 
dubbing, and whitening upper 
leather, and giving the leather a 
" satin finish," 504, 505 
Raising by sour tan-liquor, 301, 302 
by yeast, 302 
the hides, 2G3 
with barley, 300 

with sulphuric acid, MacBride's 
discovery of, 58 
Ratanhy red, 122 

root, 121 
Raw materials of the tanner, 93 
Raw skins for Erlanger leather, the 
kind required, and the modes of 
buying and preserving, 643-647 
Realgar, 51 

Receipts for various vegetable colors 
and for coloring leather with mine- 
ral pigments, 732-736 
Red ulazarine, 735 
aniline, 743, 744 
for skivers, 752 

madder, on oil leather, 737, 738 
oak bark, 119 

prussiate of potash, 719, 720 
Reddish shades with, aniline, 756 
Reds, 734, 735 

Reel for handling in the lime vats, 266 
hand for handling hides, 352, 353 
Reimer and RoUet on the intercellular 
substance in skin, 97 
on the formula of coriin, 84, 85 
on the matter extracted from skin, 
99 
Reinsch on the tannin in tormentil 

root, 122 
Removing extractive matter from 

tanned leather, 503, 504 
Renewing the surface of japanned 

leather, 592 
Reseda luleola, 118 
Resin and fat in leather, determina- 
tion of, 81, 82 
Resinous gums and floating particles, 
removing from bark extract, 227 
substances in tannin, effect of, 127 



Resins and camphor tannins from, 138 
pectine substances but little studied 
by chemists, 113 
Rete Malpighianum, 94, 95 
Reusch in regard to the strength of 

Klemra's oil leather, 694 
Rhinoceros, 45 
Rhus species, 116 

Richardson, Alpha, first splitting ma- 
chine patented by, 1831, 369 
Richardson's union splitting machine, 
" 369-371 

Richter's process for forming a solu- 
tion for tawed leather, 769, 770 
Rinsing and soaking for glove leather, 

648 
Rio Grande, quality of hides from, 41 
Roan, 70 

Roberts and Lenox's fleshing, slat- 
ing, and striking-out machine, 332, 
333 
Robinson's depilatory process, 269 

tanning process, 603, 604 
Robiquet and Boutron's apparatus, use 
of, in extracting gallotannic acid, 
103, 104 
Rochleder and Kawalier on tannopinic 
acid, 109, 110 
on the action of alkalies on 

tannin, 107 
on the treatment of tannin 
Avith hydrochloric acid, 107 
on the tannic; acid in the horse 
chestnut, 120 
Rock oak bark, 1 1 9 
Rocker handles for handling hides, 353 
Rock's liquid for curing hides, com- 
posed of pyroligneous acid, aloes, 
and alum, 52, 53 
Rollers for polishing glove leather, 

661-668 
Rollet and Reimer on the intercellular 

substance in skin. 97 
Rolling leather, machines for, 453-468 
patents for machines for, 467, 
468 
machine for rolling sole leather, 
485, 486 
Roots, tannin of, 121, 122 
Rosaniline, 743 
blue, 742 
green, 742 
. violet, 741, 742 
Rose, Bengal, for skivers, 753 
color, 724 
pink for skivers, 750 



INDEX. 



811 



Roseine, 743 

Rossing bark, 181, 182 

machines, patents for, 182 
of bark before and after shipping, 
181, 182 
"Rotten" or "burned" leather, 677 
Rove, 115, 116 
Rubine, 743 

Riiemelin's tan vat, 607, 608 
Rufitannic or tannoxylic acid produc- 
tion, composition and formula of, 
110 
Running water, soaking dry hides in, 

243 
Russet, 70 

Russia and Morocco leathers, dyeing 
with aniline colors, 754-758 
consumption of hides and skins in, 

66 
decline of Morocco manufacture 

in, 66 
exports calf-skins to Germany and 

France, 41 
leather, 574-582 

artificial, 581, 582 

at the centennial exhibition, 

575 
black, coloring, 578 
coating with gum tragacanth 

solution, 578 
dye for, 576 
dyeing, 576-578 
hides used in the manufac- 
ture, 575 
imparting the odor of, to arti- 
ficial leather, 582 
its (]ualities and places of pro- 
duction, 67, 68 
mordant used in Russia in 

dyeing, 576-578 
name and origin, 574 
not now much used in public 
libraries in the United 
States for bookbinding, 67 
odor of, produced by birch 
bark, 755 
similar to, imparted by 
Lombardy poplar bark , 
119 
period of tanning, shortening 

the, 576 
process of manufacture as 
practised in the United 
States, 575-578 
red G light aniline dye, 755 
R dark aniline dye, 755 



Russia leather, red — 

G R medium aniline 
dye, 755 
uses of, 574 

willow bark used for tan- 
ning, 121 
oil, manufacture of, 578-581 
tanning in, 66 

wealth of, in fur-bearing animals, 
G6, 67 
Rust yellow, 734 
Rutea, 114 

formosa, 114 



SABATHE and Jourdan's process 
for preserving hides and skins, 53 
Saccharine substances, use of, in bat- 
ing, 346 
Sacc's process for preserving hides and 

skins, 53 
Safhan leather, 70 
St. Crispin, who stole leather to make 

shoes for the poor, 58 
St. Real, 58 
Sal ammoniac, 714 

its use in determining the 
percentage of lime in 
leather, 83 
Salem, Mass., the upper leather pro- 
duced in, 493 
"Salem tan press," 508-511 

Weston's, 508-511 
Salicylic acid for preserving hides, 50 
Saiix alba, 1 20 
arenaria, 120 
fragilis, 120 
purpura, 120 
Salt, common, 135, 136 
for tawing, 654 
the most simple and cheapest 

means of preserving hides, 50 
use of, in separating coriin, 97, 99 
use of, in sweating fresh hides, 299 
used for tawing, 64 
Salted calf-skins, liming, 264, 265 
hides, softening, 241 
treatment of, 242 
Salting hides, 49, 50 

Delane's method of, 49, 50 
Saltpetre, 53 

in tanning, 239 

use of, in soaking hides and skins, 
239, 240 
Salts, 711 

chromium, 133, 134 



812 



INDEX. 



Salts- 
ferric, 135 
Salzburg vitriol, 712 
Salzer's test of Schulze's .method of 

determinino; tannic acid, 14G 
Sap green, 734 
Sassafras root, 122 
Satin finish on leather, 504 
Saturation of skin, moment of, accord- 
ing to Muntz and Schon, 129 
Saw-tooth flesher for dry hides, 309 
Sawyer's leather measuring machine, 

473-479 
Scarlet, 735 

No, 2, for skivers, 754 
Schlosser's composition for depilating 

green and dry hides, 272, 273 
Schmidt's description of Aikens's 
method of working lamb- 
skins into glove leather, 
(i64-<]6G 
of Watts' s method<)f working 
the skins of lambs, goats, 
and dogs into glove leather, 
6G6, 667 
Schrilf's investigation in regard to 

gallotannic acid, 1 08 
Schulze's Investigations in regard to 
the tannic acid yielded by oaks of 
different ages, 112, 113 
Schulze's method of determining tan- 
nic acid, 145-147 
Science and the art of tanning, 59, 60 
S(!orza rosa, 121 

Scourer and setting machine, Lock- 
wood, 386-392 
use of. In Massachusetts, 
388 
Scouring, 385-407 
after bating, 337 
and setting machines, patents for, 

407, 408 
brush, 385 
by hand, 385, 386 
dressing, setting -out machines, 

Burd'on, 401-405 
machine parts. Holmes, 396, 397 
setting, and hide-working ma- 
chine, the Holmes, 392-398 
slicker, 337, 338 
table, 386 
upper leather, 337 
Scraping and stretching upon the grain 

side for cliomois leather, 681 
Sea green, 723 
Seal-skins, 43, 44 



Seasoning straight grain goat, 533 
Seasons and place at the time of bark- 
ing. Influence of, on the richness in 
tannin, 177 
Sebaceous glands, 95 
Sebacic acids, how determined In de- 
termining the percentage of fat In 
leather, 84 
Seguin, 58 

Seguin's system of quick tanning, 58 
Selecting hides and skins, 47, 48 
Setting and scouring machines, pa- 
"tents for, 407,^408 
scouring, and hide-working ma- 
chine, the Holmes, 392-398 
machine and scourer, Lockwood, 

386-392 
out, scouring, and dressing ma- 
chine, Burdon's, 401-405 
Sewlno- goat- skins for tanning, 527 

machine for sewing goat-skins, 527 
" Shades," 703, 704 
"Shading" a defect In leather, 676, 677 
Shagreen leather, 65 

qualities and places of jwoductlon 
of, 67 
Shark-skins, 45 
Shaving, whitening, and buffing leather, 

patents for machines for, 430 
Shaw's compound for finishing upper 

leather, 450 
Sheep, Importance of, as sources of 
leather, 42 
skin fleshers' dressing. Hart's pro- 
cess, 557, 558 
for linings, binders, and 

skivers, 555-558 
treatment of, 556 
tannery, drying loft of, show- 
ing the skins hung up 
to dry, 556 
exterior perspective view 
of, showing the slat 
openings Into the dry- 
ing loft, 556 
finishing department of, 
557 
skins, artificial, for linings, 561, 
563 
dressing, Hestal's process for, 

550,'561 
dyeing the wool on, 624-626 
Heshers, splitting, 556 
for linings, binders, and ski- 
vers, where the American 
supply is obtained, 555 



INDEX. 



813 



Sheep-skins — 

Hibbard's process for pre- 
paring and tanning, 559, 
560 
improved method for tanning 

and dressing, 558-561 
in boots and shoes, large con- 
sumption of, in Massachu- 
setts, 555 
in chrome tanning do not re- 
quire to be ireed from olea- 
ginous constituents, 62 
manufacture of, into linings, 
bindings, and skivers, im- 
portance of, 555 
removal of, from the vats and 

draining, 556 
rolling, glassing, and pebbling 

by machinery, 557 
sometimes employed for man- 
ufacturing Morocco leather, 
41 
tanned and finished by the 
employment of chromium 
compounds are not porous, 
62 
tanned and oiled, 41 

with chromium com- 
pounds, 61, 62 
with the wool on, 42 
tanning and finishing, 655- 
563 
materials and processes 
for, 556 
tawing, Manasses's method 

for, 558, 559 
their mode of treatment and 

uses, 42 
used by the ancient lonians 
and Persians to write upon, 
57 
uses of, 41 

worked up as skiver, roan, 
and Morocco, 42 
the home supply, 42 
valuable for the purposes of the 
tanner, in inverse proportion to 
their value as a source of wool, 
42 
Ships of leather, use by the Phoeni- 
cians, 57 
"Side" and "split," tanning and 

finishing the, 492-503 
Sicilian sumach, 116 
Siebel's use of refuse gas lime, 295 
Silica in gramineous plants, 175 . 



Silica — 

in the epidermis of the bamboo, 
sugar-cane, and the bog-weed, 
175 
Skin, a transverse section of, 94, 95 
animal, 93-100 
animal, construction of, 93 
connective-tissue fibres of, 96 
difference in the c[uantity of tan- 
nins absorbed by the, 125 
" Skin dressed," descriptive of the 

savage in early times, 37 
Skin fibre, important properties of, 100 
fibroin, 99 
flesh side of, 94 
for Morocco tanning, preparation 

of, 525-527 
"grain side" of, 94 
influence of, on the quality of 

leather, 94 
intercellular substance in, 97 
moment of saturation of, for tan- 
ning, 129 
structure of, and its behavior with 

reagents, 93 
table of the strength of, in differ- 
ent places, 91 
tables showing the quantity of 

tannin absorbed by, 125-129 
the chemical and morphological 

constitution of, 96, 97 
use of, in determining tannic acid, 
140 
Skins and hides, 33-55 

coloring partially tanned, 773 
consumed in the United 

States, 75 
important points in flaying, 

46 
preserving them, 50-52 
removing from animals, 45- 

47 
selection, 47, 48 
washing and soaking, 237- 

243 
Wickersheimer's process for 

preserving, 53, 54 
with the hair on. Carter 
and Keith's process for 
tanning, 621, 622 
and peltries, processes for soften- 
ing, 243-246 
artificial tannins used for tannine, 
137 ^ 

class of, to which tawing is ap- 
plied, 64 



814 



INDEX. 



Skins — 

cleaning before dyeing, 721 

decompose if moist, 96 

do not absorb an unlimited amount 

of tannin, 129 
for glove calf, and glove sheep, 

whence obtained, 525 
for glcve leather, manner of work- 
ing, 647 
influence of hard water on, 98 
light, for car seats, etc., prepar- 
ing, coloring, and polishing, 
770 
tanning with the hair on, 
Johnson's process, 620, 621 
numbers of, consumed in Russia, 

66 
obtained by crossing of he goats 

and ewes, 644 
of animals, used as apparel of the 

people, 36, 3 7 
of interest in connection with the 

leather manufacture, 36 
of the mammalia class of animals, 

36 
of young animals, necessity of 

handling carefully, 675 
or hides with the wool, hair, or 
fur on, Coe's process for tan- 
ning, 621 
those of calves, sheep, goats, deer, 

pigs, seals, etc., 39 
with hair and fur on, tanning and 
coloring, 620-626 
Skirtings, 41 
Skiver, 70 
Skivers, sumach tanned, dyeing with 

aniline color, 748-754 
Sky blue, with mineral pigments, 736 
Sky's artificial tanning material, 137 
Slating goat-skins, 527 
Slicker, French whitening, 423 

glass, for glassingleather by hand, 

453 
scouring, 337, 338 
Slickers, curriers', patents for, 430 
Sliming lamb-skins, 664 
Smith's compounds for producing imi- 
tation of grain and Morocco 
leather, 551, 552 
leather whitening and buffing 

machine, 428, 429 
preparation of tan-bark for trans- 
portation, 182, 183 
Smutting and blacking appliances, 
440-449 



Smutting — 

leather, 447 

machine for, Bryant's, 447- 
449 
Snouba bark, 121 
Snyder's tanning process, 598 
Soaking after fleshing, the length of 
time for, 312, 313 
and rinsing for glove-leather, 647, 

648 
and washing hides and skins, 237- 

243 
dry hides in running water, 243 
final, before placing the hides in 

the ooze, 338 
hides after fleshing, 311-313 

after fleshing, importance of, 

311 
and kips in foul, bloody water, 

241 
and skins, injuries which 

arise in, 238 
in a steeping cistern after 

fleshing, 312 
in France and Germany, 312 
putrid, 312 
Soaks, for dyeing, 720, 721 

for hides for upper leather, 495 
for skins for Morocco tanning, 525 
period which the hides should re- 
main in the, 241 
Soap and oil blackings, 449 

iron, Knapp's, in tanning, 630 
metallic, 53 

solution, for determining the hard- 
ness of water, 170 
Soda, 718 

alum, 713 

and sulphuret of calcium for de- 
pilating, 287 
as a substitute for potash, in the 
manufacture of chamois leather, 
686 
caustic, depilation by, 290 
lime, its use in determining nitro- 
gen in leather, 84 
lye, its use in determining the per- 
centage of fat in leather, 83 
muriate of, super-tartrate of po- 
tassa and tartaric acid, as a 
bating compound, 342, 343 
Soderberg's bating process, 349 
Sodium and calcium, as a depilatory, 
276, 277 
bicromate, 134 
.carbonate, 718 




INDEX, 



815 



Sodium — 

(.•Hvbonate, use of, in determinirg 

tannic acid, 144 
chloride in tanning, 633 
chloride of, Gl, 62, 715 
hydrate, 709, 710 
Sodom and Gomorrah, 35 
Soerensen's process for dyeing leather, 
by subjecting it to the action of 
A'anadic compound, 764 
Soft leather for gloves, 642 
Softening dry hides, skins and peltries, 
by soaking them in the waste 
water from gas works, 243, 245 
hides, mill for, 256-258 

skins, and peltries, processes 
for, 243-246 
machine, Tidd's, 570-572 
plumping and depilating hides and 
skins with sulphide of barium, 
282 
salted hides, 241 
the skin after dyeing, 731, 732 
Softness, to restore, to dyed oil leather, 

739 
Sole leather, 481-491 

artificial, 489-491 
inside tanning, 486, 487 
tanned with (.-hestnut oak 

bark, 119 
tanning and finishing oak 

slaughter, 483-486 
varieties of, in the United 

States, 482 
what is sought to be com- 
bined in, 481 
what is understood by, 481 
leathers, classification of in the 
United States, 482 
Soles of boots and shoes, compound 
for changing the color of, 7 73, 
7 74 
Solferino, 743 

Soluble blue for skivers, 752 
Solutions for staining tawed leather, 

769, 770 
Sorting kid and lamb-skins, 644 
Sour liquor, plumping with, 360, 361 
liquors, Botchford's process of 
distilling, in order to get rid of 
decaying animal and vegetable 
substances, 360, 361 
tan-liquor, raising by, 301, 302 
South America, goat-skins of, 42 

American climate, effect of, on 
the hides of the cattle, 40 



South American hides, how classified, 
whence received, and their qualities, 
40, 41 
Spanish sumach, 116 
Spectrum, 698, 699 

colors contained in the, 701 
Spent tan, utilization of, 507 
Spill & Co 's vegetable leather, 72, 73 
Split calf-skins, sometimes used for 
Morocco, 41 
finishing of the, 500 
grain and bufi' leathers, 511, 517 
leather, 71 

compound for finishing, 451 
prejjaring the surface of 
japanned or enamelled 
leather, 592-594 
Splitting hides for patent leather, 587 
when done, 493 
leather, 368-384 
machine, belt knife, 378, 379 

Enos's attachment to prevent 
injury to the arms of work- 
men, 371-375 
Flanders and Marden's belt 

knife, 369 
McDonald and Beggs', 375- 

378 
Richardson's Union, 369-371 
machines, 36 9-384 

belt knife, Cummings's im- 
provement in, 380-383 
facilities afibrded by, 369, 370 
patents for, 383, 384 
Sponhouse's method of manufacturing 

water-proof leather, 505-507 
Spring and fall, tannin in oak-bark in 
the, 177 
the propel' time for j)eeling bark, 
176 
Sprinklei', hanging, 208 
leach, the, 203, 204 
should be run slowly in the leach, 
221 
Stack's bating process, 345, 346 
Staining tawed leather, solution for, 

769, 770 
Stannic chloride, 714 
Stannous chloride, 141, 714 
Statistics of the tanning industries of 

the United States, 74-80 
Steam, boxes for exhaust and direct, 
216, 217 
depilating with, 270, 271 
exhaust, regulating the supply of, 
218 



816 



INDEX. 



Stearine in spirit of wine for produc- 
ing white glazed leather, 697 
Steeping cistern for soaking hides after 
tleshing, 312 
cisterns in France and Germany, 
312 
Steinmann's apparatus for handling 
hides in the lime pits, 26G-269, 357 
Stenhouse on myrobalans, 117, 118 
on quercotannic acid, 110 
on the tannic acid contained in 
Sicilian sumach, 117 
Stoning machines, patents for, 465-467 

out, 431 
Strabo on the early clothing of the 

people, 37 
Straight grain goat finishing, 532—535 
Straining cloth of the supply tank of 
leaches, 214 
the liqnors going into the leaches, 
213, 214 
Strecker on tannin as a glucoside, 106, 

108 
Strength of chrome leather and tanned 
^leather, 638-6^0 
of leather, testing, 89-92 
of skin in different places, table 
of, 91 
Stretching and scraping upon the flesh 
and grain sides for chamois 
leathe'r, 681 
capacity of chrome leather and 

tanned leather, 638-640 
iron, 687 

leather, ajjparatus for, patents 
for, 596 
Oliver and Howell's machine 
for, 588, 589 
machine. Coupe's, 568, 569 
the hides for patent leather, 588 
Striker applying to the skin, 730, 731 
Strikers, 729 

Striking out and drying skins for 
Morocco, 530 
fleshing, and slating machine, 
Roberts and Lenox's, 332, 
333 
Strontium, 134 
Study's conti-ivance for liming hides, 

357 
Stufhng and stuffing wheels, 408, 409 
compound, Thayer's, 418, 419 
Williams's, 417-420 
"B. S." oil for, 419, 420 
leather, patents for, compounds 
for, 420 



Stuffing — 

the split, 500 
Substitute for patent leather, 595 
Sugar cane, silica in, 175 
Sugar of lead, 98, 716 

used by TurnbuU in bating, 336 
use of, in bating, 346 
Sulphate, ferrous, 711, 712 
of alumina, 61, 62 
of copper, 52 
of iron, 52 

tanning, 629 
of sodium and calcium as a depila- 
tory, 276, 277 
Sulphates, 711-714 
Sulphide of barium for softening, 
plumping, and depilating hides 
and skins, 282, 283 
of calcium for depilating hides 
and skins, 283 
Sulphur and lime, action of, in depila- 
ting, 283 
dioxide and water for bating, 346- 
349 
Sulphuret of calcium and soda, depila- 
ting with, 287 
for depilating hides and 
skins, 283" 
Sulphuretted hydrogen gas for depila- 
ting and swelling hides, 273, 274 
Sulphuric acid, 105, 706 

and lime liquor for bating, 

344 
as a test for barium salt, 86 
composition, formula, action, 
and specific gravity of, 363 
concentrated, 130 

used in preparing arti- 
ficial tannins, 137 
early use of, by tanners, 362 
for bating, 336 
fraudulently increasing the 

weight of hides by, 49 
in plumping, proportions of, 

362 
Nordhausen, or fuming. 706 
jdumping with, 361-363 
precautions to be taken with 

in plumping, 362 
pure dilute for analysis, 156 
raising with, MacBride's dis- 
covery- of, 58 
use of in plumping, 359. 
360 
Sulphurous acid and lime-water as a 
dejjilatory, 278 



INDEX. 



817 



Sumach for gi-ain, split, and buff' 
leathers, 511 
its use in tanning, 125 
Kathreinev's determination of tan- 
nic acid in, 158 
leather prepared with, qualities 

of, 117 
native use of in the United States, 

598 
varieties and qualities of, 116, 117 
Sumach-tanned leather, 64 

skivers dyeing with aniline 
colors, 748-754 
Supei'-tartrate of potassa, muriate of 
soda and tartaric acid as a bating 
compound, 342, 343 
Supply tank for leaches, 213 

of leaches, heating while 
leaching is not going on, 
215 
Surface of split leather, preparing for 
manufacturing japanned or enam- 
elled leather, 592-594 
Swan's bating process, 350 
Sweat-box for warm sweating, 298 
Sweat glands, 95 

Sweating, care to be observed in, 296- 
298 
depilating by, 291-300 
fresh hides, "299, 800 
hides, 241 

and skins, building for, 293- 
295 
large hides, 296, 297 
process, cold, 291-293 

employed in Germany and 
other parts of Europe, 
298 
how it acts on the hides, 

296 
warm, 298, 299 
small hides and kips, precautions 
to be taken in, 296 
Swedish glove-leather, willow-bark 
used for tanning, ] 21 
leather, imitation of dyeing, 723 
sumach, 117 
Swelling and depilating hides with 
sulphuretted hvdrogen gas, 273, 
274 
hides, MacBride's discovery of 
the use of sulphuric acid for, 
58 
or plumping, 359-363 
the essential action of, 359 
Swiss goat-skins, 43 
52 



TABLE for leather scouring ma- 
chines, Daheney's, 405-407 
of Schwarz & Co., showing the 
strength of skins in different 
places, 91 
of specific gravity and pei'centage 

of tannic acid, 145 
of the quantity of tannin required 
for the conversion of one pound 
of skin into leather, 125, 126 
showing the capacity of leaches of 

different sizes, 213 
with bed of zinc for dyeing skins, 
721, 722 
Tables of the percentage of tannin in 
various tanning materials, 123, 124 
Tallowed leather currying, 523 
Tan-bark, chestnut oak, 483 

grinding, cutting, and crush- 
ing, 184-200" 
preparing for transportation, 
182, 183 
leather, behavior of, in water, 89 
of, toward boiling water, 
as a test of tanning, 
85, 86 
liquor, sour, raising by, 301, 302 
tannic, gallic, and acetic 
acids in, 360 
meter, the, 139 
press, Daniels's, 508 

Holmes's, 507, 508 
presses, economy in the use of, 607 

improvements in, 507-511 
spent, as a fuel, 507 
tubs in a Morocco factory, view 

of, 527 
vat, Rueraelin's, 607, 608 
Tanned leather, classed as hides, kips, 
and skins, 38 
effect of water on, 637-640 
Tanner, a, named by Homer, 57, 58 
Tanneries and other places where skins 
are stored, disinfecting, 48 
in the United States, products of, 
75 
Tanners, the Tui'ks, Russians, and 
Hungarians the most celebrated in 
the first centuries of the Christian 
era, 65 
Tanners' vats, agitators, and handling 

appliances, 358, 359 
Tannic acid a primary product of ve- 
getable life, 113 
Carpene- Bai'bieri's method 
of determinintr, 143 



818 



INDEX. 



Tannic acid — 

colorimetric method of deter- 
mining, 142 

contained in Sicilian sumach, 
accoi'ding to Stenhouse, 
identical with tannic acid, 
117 

Davy's volumetric method of 
determinino-, 139 

estimation of, by means of its 
specific gravity, 139 

extractive substances exert a 
material influence upon the 
value of a, 113 

Fehbei'g's volumetric denom- 
ination of, 140 

Fehling's method modified by 
Muller of determining, 143 

fermentation of, by fungi and 
ferments, 112 

Fleck and Wolf's method of 
determining, 141 

gallotannic acid and that de- 
rived from East India kino 
are the same, 114 

Gerland's method of deter- 
mining, 144 

Hammer's method of deter- 
mining, 144 

in acicular form, obtaining, 
232-234 

in bark decoction, to deter- 
mine with solution of po- 
tassium manganate, 162, 
163 

in tanning materials, deter- 
mination of, 139-164 

in the presence of indigo solu- ; 
tion, 154 

Jeans's method of determin- 
ing, 144 

loss of, by the use of hard 
water, 112 

Mlintz and Rampercher's ap- 
paratus for determining, 
140 j 

of the aqueous solutions, sepa- > 
ration of, 105 1 

or tannin, 100-113 

Persoz's method of determin- ' 
ing, 141 I 

physiological and pathologi- 
cal, 102 

precipitation of, with cupric 
acetate when testing for 
grape-sugar in leather, 86 



I Tannic acid — 

propertj^ of, of forming in- 
soluble combinations with 
earthy alkaline salts, 112 
use of, in preparing connec- 
tive-tissue substance, 97, 99 
I various kinds of sumach pro- 

bably contain different va- 
rieties, 11 7 
which, when heated, forms 
pyrogallic acid, the leather 
produced by, 113 
Wildenstein's method of de- 
termining, 142 
yielded by different plants at 
different stages of growth, 
and by different parts of 
the same plant, 112, 113 
acids of the horse chestnut, 120 
our knowledge of, very in- 
complete, 102, 103 
varying action of different 

kinds on skin, 113 
which have not been thor- 
oughly examined, 110 
yielded by oaks of different 
ages, 112, 113 
Tannin, 107 

action of, on hides, 363, 364 
behavior of, towards various sub- 
stances, 106-108 
chromic acid in aqueous solution, 

while hot, decomposes, 107 
decomposes at about 410° to 419° 

F., 105 
free from sugar synthetically pre- 
pared by Schriff', 108 
from gall-nuts, form and charac- 
teristics of, 105 
from wood of the live oak, 122 
gall-nuts yield the richest, 114 
Holtz's apparatus for obtaining a 

pure and soluble, 232-234 
importance of, to the tanner, 100 
in alder bark, 121 
in chrome leather, experiment of 
Dr. Clark in regard to, 636-640 
in oak bark in the spring and fall, 

177 
in oak-tanned leather, two and 
three years respectively in th(^ 
pit, 129 
in ratanhy root, 121, 122 
in tanning materials, comparison 
of results obtained by several 
described methods, 163, 164 



INDEX. 



819 



Tannin — 

in various tanninj^ materials, tables 

of, 123, 124 
in willow barks, 120, 121 
it is yet a question whether it can- 
not be produced by artificial 
means, 60 
melting and decomposition of, 105 
new formula of confirmed, 109 
not a glucoside, 107 
not absorbed in unlimited quanti- 
ties by the skin, 1 29 
of hemlock bark, 119 
of horse-chestnut bark, 120 
of oak barks, 119 
of protaceaj barks, 121 
of ratanhy root, 121 
of the gall-nut, 103 
of the scorza rosa, 121 
of various kinds absorbed by skins, 

12G-128 
of willow bark, 121 
or tannic acid, 100-113 
percentage of, in leather, 1 28 
reduces permanganate of potash 

solutions, 107 
should be digallic acid, according 

to Schritf.'^lOB 
solution, preparation of, for de- 
termining tannic acid, 155 
solutions, impure, modify them- 
selves in contact with the air, 1 08 
the number of plant substances 

containing, 100, 101 
transformation of, into gallic acid, 

106 
under the form of a polygallic 
glucoside, 109 
Tanning, ancient, oriental, 65 
aluminium, 641 
, and coloring beaver, otter, and 
other skins with hair or fur 
on, 622-624 
and coloring hides and skins with 

hair and fur on, 620-626 
and finishing grain, split, and buff 
leather, 511-517 
imitation French kid, brushed 
kid, straight grain goat, 
pebble goat, and oil goat, 
524-535 
oak slaughter sole leather, 

483-486 
sheep-skin fieshers for linings, 
binders, and skivers, 555- 
-558 



Tanning and finishing — 

sheep-skins, 555-563 
the "side" and "split," 492- 
503 
apparatuses for goat- and sheep- 
skins, 536-545 
based rather on physical action 
than on chemical reaction, 364 
by Klemm's process for oil leather, 

693-697 
constituents of leather, 82 
establishments in tlie United 

States, 75 
improvements in, largely mechani- 
cal, 59, 60 
in the United States, capital in, 
75 
rank of different States 
in, 76 
influence of increase in popula- 
tion and wealth on, 65 
inside sole leather, 486, 487 
interests in the United States, 

statistics of, 74-80 
knowledge of the structure of the 
skin, and its behavior with re- 
agents, importance of, 93 
known in the time of Moses, 56 
liquor of Triedel and Molac, for- 
mula of, 627 
material for Morocco, 525 
materials for sheep-skins, 556 

generally used in this country, 

481 
generally used in various 

countries, 124, 125 
mineral, 130-136 
the most important, 1 1 3 
various, table of tannin in, 

123, 124 
vegetable, 100-129 

chemical examination of, 
138-164 
mineral, 626-641 
Morocco by the hand method, 541, 
542 
in combined wheel and vats, 
542-545 
origin of the art of, 37 
or tawing, Heinzerling's process 

of, 61-63 
process, Daniel's, 600 
Enos's, 599 
Garge's, 602 
German's, 598 
Gould's, 599, 600 



820 



INDEX. 



Tunning process — 

Hatch's, 600 
Hibbard's, 598, 599 
Irving's, 598 
Jenkins's, 60G, 607 
Keeler's, 599 
Kennedy's, 600, 601 
Kidder's, 606 
Noble's, 601, 602 
Page's, 602 
Pickard's, 605 
Robinson's, 603, 604 
Snyder's, 598 
the theory of, 363-365 
Wattles' s, 599 
what it consists in, 598 
Wheelock's, 605, 606 
Wyeth's, 604, 605 
processes, 597-609 

generally followed in the 

United States, 597 
large numbers which have 

been invented, 597 
patent, precautions to be 

taken in using, 597 
patents for, 609-614 
science has not done its duty in 

regard to, 59, 60 
sheep-skins, Hibbard's process for, 

559, 560 
substance in leather, determina- 
tion of, 85 
substances artificially prepared, 
136-138 
mineral and artificially pre- 
pared, 130-138 
synopsis of the history of, 56-63 
the most widely spread, and best 
developed industry of Russia, 
66 
the oldest method of. Go 
upper heavy leather, details of, 

495-507 
what it consists of, 63 
with chromates, Henzerling's 
method of, 633-641 
ferric salts, 626, 627 

Knapp's processes, 628- 
633 
Tannins, absorbed by the skin, varia- 
tion in the f[uantity of the dif- 
ferent, 125 
former classification of, 101 
obtained by treating peat, brown 
coal, coal, etc., with nitric acid, 
138 



Tannins — 

profluced by the action of sul- 
phuric acid on I'esins and cam- 
phor, 138 
quantities of, required for the con- 
version 1 lb. of skin into leather, 
125, 126 
variation in the chemical and 

physical behavior of, 101 
which precipitate the ferric salts 
blue, 101 
ferric salt green, 101 
Tannomelanic acid, 109 

composition and formula of, 

109 
how obtained, 109 
Tannopinic acid, 109, 110 

formula of, 110 
Tannoxylic, or rufitannic acid, pro- 
duction, composition, and formula 
of, 110 
Tapley's unhairing machine, 318-322 
Tartar, chemical action of, 717 
crude, 717 
emetic, use of in determining 
tannic acid, 144 
Tartaric acid, 709 
Tartrates, 717 
Tawed leather, Richter's solution for 

staining, 769, 770 
Tawing, 642-697 

aluminium acetate preferable to 
aluminium sulphate or alum for, 
132 
aluminium alum less desirable than 

chromates for, 1 34 
and dressing sheep-skins, im- 
proved methods for, 558-561 
chromium alum the most import- 
ant salt used for mineral tan- 
ning and, 134 
class of skins to which it is ap- 
plied, 64 
difference between Aikens's and 

other methods, 665, 666 
fluids, Jennings's, 669-671 
French or Erlanger method of, 

642-668 
hides and skins, patents for, em- 
ploying mineral substances for, 
641 
introduced into Hungary before 

the 12th century, 64 
Jennings's method of, 669-673 
material used for hides for patent 
leather, 585, 586 



INDEX. 



821 



Tawing — 

01' tanning, Heinzerling's pi'ocess 

of, Gl-63 
paste, object of using, G57— 061 
pastes for glove leather, 653-661 
jiotash alum used in, 132 
practised by the Romans who 

derived it from Africa, 64 
Preller's method of, 689-693 
sheep-skins, Manasse's method 

for, 558, 559 
what it is, 64 
Taylor's machine for unhairing, desh- 
ing, and working hides and skins, 
32'7-329 
yerniinalin cliehula, 117 
Terra ja})onica, 1 1 4 

adulterations in, detection of, 

114 
discovery of, the tanning jiro- 
perty of, 58, 59 
Terreil's modification of Mittenzwei's 
method of determining tannic acid, 
149 
Tesera sumach, 116 
Testing leather, physical methods of, 
86-92 
the strength of leather, 89-92 
Tests for detecting the fraudulent in- 
creasing of the weight of hides, 49 
Thayer's stuffing compound, 418, 419 
Thompson and Johnson's bark mill, 

190-195 
Thymol, 54 

Tice and O'Connell's process for finish- 
ing lower grades of leather similar 
to Morocco, 552-555 
Tidd's softening machine, 570-572 
Tigris and Euphrates, valley of, hair 

and wool industries in, 36 
Tin bath for coloring partially tanned 
hides and skins, 773 
composition, 714 
salt, 714 
Tinnerholm's compound for whitening 
leather, 774 
depilatory process, 281-284 
Titre, making the, 156 
Tools used in barking, 177, 178 
Tormentll root, 122 
Towein's graining machine for Russia 

leather, 578 
Tragacanth solution for giving a bril- 
liant appearance to Russia leather, 
578 
Train oil, 64 



Trajan's Forum, marble bust of a skin 
dressed savage found in, 37 

Transportation of tan-bark, 182, 183 

Troy or Starbuck bark-mill, arrange- 
ment of, 185 

Tucker's bating process, 350 

Turly's bating process, 351 

TurnbuU's plan for submerging goat- 
skins, 629 

Turning steels, 309, 310 

Tui'pentine, 69 

use of, in determining the percent- 
age of fat in leather, 84 

Twisted leather, 689 

Tyralline, 743, 744 

Tvrol sumach, 116 



ULMIC MATTP:R, 107 
Ulinus campestrifi, 119 
Uncara gainhir, 114 
Unhairing and fleshing, 304-330 

as practised in France, 306, 

307 
by machinery, 313-333 
hides and skins simultane- 
ously, Janson's machine 
for, 330-332 
nnu.'hines, patents for, 333- 

335 
of hides, the most laborious 
operations in tanning, 313 
by the hand process, 304-308 
fieshing, and working hides and 
skins, Taylor's machine for, 
327-329 
goat, calf, and sheep-skins, 526 
laides and pulling wool. Mower's 
process for, 278-281 
and skins, composition for 
preserving and, 50-52 
how usually effected, 

304, 305 
by machinery an accom- 
plished fact, 313 
knife, 304-306 

handling the, 305, 306 
machine, Larrabee, 314-318 
McDonald, 322-329 
Tapley, 318-322 
machines, McDonald's improve- 
ment in feed-rolls for, 325-327 
Union tannage, 119, 481 

light liquors used in, 489 
slaughter leather, varieties of, 
482 



822 



INDEX. 



United States, cattle ranches in, 35 

statistical facts relating to 

currying in, 79 
statistical facts relating to 

tanning in, 75 
Upper leather, compound for finish- 
ing, 450 
Head's process for soaking, 

liming, tanning, blacking, 

and gumming hides for, 

500-503 
hides for, green shaving and 

placing in the bate, 312, 

313 
tannery, cellar of a, 368, 369 
what comprised under this 

head, 492 
leathers, the hides from which 

they are produced, 492 
use of lime with, 492 



VAC HE-LEATHER, preparation 
of, 519, 522 
Valonia, 117 

where used for tanning, 125 
Various machines for putting out 

skins, 545, 546 
Varnish for patent leather, 592 
Varnishing leatlier, the art of, 59 

patent leather, 592 
Vat and wheel combined for tanning 
Morocco, 542-545 
or tank with feeding pipe for 
Morocco tanning. Baker's, 527, 
528 
tan, Ruemelin's, 607, 608 
Vats, agitators, and handling appli- 
ances, patents for, 358, 359 
for hides for patent leathei-, 586, 

587 
in which the England wheels 

revolve, 355, 356 
of sumach leather for goat-skins, 
527 
Vauquelin, 58 
Vegetable colors, 732-735 
kingdom, 35 
leather, 72, 73 
tanning materials, 100-129 

chemical examination of, 
138-164 
Verdegris, 716, 717 
Vickers and Holmes's bating composi- 
tion, 344 
Victoria green for skivers, 750 



Vinegar wood, use of, with sour tan 

liquor in plumping, 359 
Violet, 724, 734 

aniline, 741, 742 

color on Morocco, 757 

Hofmann's, 741 

Parisian, 741 

Perkins's, 741 

rosaniline, 741, 742 
Vision, 698 
Vitriol, blue, 712 

green, 711, 712 

or sulphuric acid for plumping, 361 

Salzburg, 712 

white, 712 
Von Hildebrant, 59 

Meidinger, 58 



WAGNER on the use and value of 
tannin, 102 
Wagner's classification of tannic acids, 
102 
method of determining tannic 
acid, 151-153 
Walker's process for gilding and orna- 
menting leather for susj^ender ends, 
765 
Wallaby skins, 45 
Walnut bark, 119 
Walrus hides, 45 

tanned with chromium com- 
pounds, 61, 62 
Walters' s filling cup for Morocco manu- 
facturers, 529, 539-541 
Ward's depilatory' process, 269 
Warm sweating process, 291, 298, 

299 
Warner's apparatus for tanning goat- 

and sheep-skins, 536-539 
Warrington, carbonate of ammonia 
employed by, for accomplishing the 
purposes of the bate, 336 
Wash leather, 71, 6 79 

wheel in a Morocco factoiy, 525 
Washing and soaking hides and skins, 
23 7-243 
goat-skins, 526 

wheel for glove leather, used in 
Germany and France, 650-652 
Water, 165-173 

analysis, AVanklyn and Frankland 

on, 169 
as a leaching fluid, 221 
change in volume, and ability of 
leather for resisting, 87-89 



INDEX. 



823 



Wjiter— 

determination of pei'raanent hard- 
ness of, 173 
of total hardness of, 171-173 
eflfect of different inorganic con- 
stituents of, upon the depilated 
skin, 167 
filtering through exhausted tan, 

112 
for cold sweating process, 292 
from gas works for softening dry 
hides, skins, and peltries, 243- 
245 
general remarks concerning, 165- 

169 
hard, loss of tanni(! acid by the 

use of, 112 
importance of a uniform tempe- 
rature of, in the manufac- 
ture of waxed-calf, 168 
of, in tanning, 165 
in an open vessel, depilating with, 

286, 287 
in leather, determination of, 82 
methods for determining the con- 
stituents of, 169-173 
process of determining the hard- 
ness of, by a soap solution, 170 
soft preferred for the manufacture 

of uj^per leather, 167 
supply of a tannery, 168 
the effect of soaking chrome tan- 
ned leather in, 637 
the temperature of, importance of, 

in tanning, 167, 168 
to the dyer, wliat white color is to 
the painter, 700, 701 
Waters, determining the cjualities for 
tanning purposes, 166, 167 
hard and soft, in tanning, 165, 166 
spring and well, constituents of, 
166 
Water-proof leather, the art of ])repar- 
ing, 59 
Morocco ware, 535 
Water-proofing, dubbing, and whiten- 
ing upper leather, 504-507 
polishing, and coloring leath- 
er, composition for, 771, 
772 
Watteau's depilatory compound, 276, 

277 
Wattles's tanning process, 599 
Watts's method of working the skins 
of lambs, goats, and dogs into glove 
leather, 666, 667 



Waxed-calf, temperature of the water 

in which the skins are soaked, 168 
Weight of hides, fraudulently increas- 
ing, 49 
Wells's bating jirocess, 350 
Weston's horizontal cylinder breaker 
bark mill, 1 85 
" Salem tan press," 508, 511 
Whang, 71 

Wheel and vat for tanning Morocco, 
542-545 
for agitating the tanning liquor in 
the vats, "586, 587 
Wheelock's tanning process, 605, 606 
AVheels, England's, time and rate of 
running, 356 
paddle, for handling hides, Eng- 
land's, 337, 355, 356 
Whip and lace leather, quick tanning 

process for, 569 
White glazed leather, by Knapp's pro- 
cess, 697 
leather, or tawed leather, 71 
vitriol, 712 
Whitening and buffing machines, 428, 
429 
buffing, and shaving leather, pa- 
tents for machines for, 430 
leather, 423-431 

compound for, 774 
the three ways of, 423 
machine leather, 424-428 
slicker, French, 423 
upper leather, processes for, 504- 
507 
AVickersheimer's process of preserving 

hides and skins, 53, 54 
Wiener's apparatus for testing the 

strength of leather, 89, 90 
Wildenstein's colorometric method of 

determining tannic acid, 142 
Williams, Moore, and Hurlburt's 

measuring machine, 469-473 
Willow bark, 120, 121 

barks, tannin in, 120, 121 
Wilmington, Del., large quantities of 

Morocco produced in, 66 
Wilson's bating process, 350 
depilatory process, 270 
Winter's leather measuring machine, 

468, 469 
Woburn, Mass., grain, split, and bufi" 

leather manufactured in, 511 
Wolff's black staining compound for 
concealing defects in leather and for 
applying to pocket-books, 762, 763 



82-4: 



INDEX. 



Wood, tannin obtained from, 122 
vinegai' for preserving hides, 50 
use of, with sour tan liquor, 
in plumping; 359 
Woodbury's process for coloring par- 
tially tanned hides and skins, 7 73 
Wool on sheep-skins, dyeing. Jack's 
method and machine for, 624- 
626 
pulling and unhairing hides, Mow- 
rer's process for, 278-281 
Working hides, Lampert's apparatus 

for, 338-341 
W^yeth's tanning 2:)rocess, 604, 605 



YEAST, raising by, 302 
• Yelk of egg, action of, in tan- 
ning,'"657-661 
constituents of, 657 
for tawing, 651-654 
Yellow, 723 

aniline, 743 

for skivers, 749 
barberry, 734 



Yellow — 

barked oak, bark of, 119 
Martin's, 757 

on Morocco, 759 
nankin, 734 

on Morocco with aniline, 755 
on oil leather, 739 
"Philadelphia," on Morocco, 756 
prussiate of potash, 719 
quercitron, 734 
ust, 734 

shade in Morocco, 757 
Yellowish-brown shades on Morocco, 
755, 756 



ZANE'S improved bark conveyer, 
200-202 
Zinaliiie, 743 
Zinc, 53 

acetate, ammoniacal solution of, 

143 
sulphate, 131, 712 
Zollickoffer's bating compounds, 341- 
343 



F. STAMM. 



JOHN BEST 



The Eureka Bark Mill Co. 




Build four sizes SOLID MILLS, 
SEGMENT MILLS, STEAM 
JACKET MILLS, for high or low 
speeds, strong or light powers, for steam, 
water or horse powers. Will dust less 
on dry or brittle bark ; gum less on 
wet or tough bark ; will grind bark that 
other mills cannot ; will grind more 
uniform, and do more work with less 
power than any mill now made. 

LEATHER ROLLER 



m^ MACHINERY. 



(See cut, page 486.) 

We make the most powerful PRES- 
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CONCAVES or BEDS, of best 
material and workmanship. Roller 
Beds planed to any radius or length of 
vibrator. 



HORIZONTAL CENTRIFUGAL PUMPS, 

"With Steam Charging- Attachment expressly for Tanners, 

May be located where most convenient, with suction pipe from cistern to pump : 
can be quickly charged with steam, and discharged through pipe or hose to any 
point desired. 




Horizontal Centrifugal Pump. 

Castings for Wet Tan-Burning Ovens. Cast-Iron Screw Conveyors. 

Tan-Packing Machines, for packing ground bark or quercitron in bags. 
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Prompt attention given to all inquiries, and orders filled at short notice. 



Address, 



EUREKA BARK MILL CO., 

Lancaster, Pa., U.S.A. 



Founded by Mathew Carey, 1785. 



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AMATEUR MECHANICS' WORKSHOP: 

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BRAMWELL. — The Wool Carder's Vade-Mecum : 

A Complete Manual of the Art of Carding Textile Fabrics. By W. 
C. Bramwell. Third Edition, revised and enlarged. Illustrated, 
pp. 4.00. i2mo ^2.50 

BRANNT. — A Practical Treatise on Distilling and the Manu- 
facture of Liquors : 
A Receipt-Book for the Preparation of all Kinds of Liquors, Cor- 
dials, Bitters, etc. Edited chiefly from the German of Dr. K. Stam- 
mer, Dr. F. Elsner, and E. Schubert, by William T. Brannt. 
Illustrated by numerous engravings. l2mo. {^In press.) 

BRANNT.— The Techno-Chemical Receipt Book: 

Containing several thousand Receipts comprising the latest and most 
useful discoveries in Chemical Technology and Industry. Edited 
from the German of Drs. E. Winckler, Heintze and Mierzinski, 
with additions by W. T. Brannt. [In preparation.) 

BROWN. — Five Hundred and Seven Mechanical Movements: 
Embracing all those which are most important in Dynamics, Hy- 
draulics, Hydrostatics, Pneumatics, Steam-Engines, Mill and other 
Gearing, Presses, Horology and Miscellaneous Machinery; and in- 
cluding many movements never before published, and several of 
which have only recently come into use. By Henry T. Brown. 
l2mo $1.00 

BUCKMASTER.— The Elements of Mechanical Physics : 
By J. C. Buckmaster. Illustrated with numerous engravings. 
l2mo $1.50 

BULLOCK.— The American Cottage Builder : 

A Series of Designs, Plans and Specifications, from $200 to ^20,00G, 
for Homes for the People ; together with Warming, Ventilation, 
Drainage, Painting and Landscape Gardening. By John Bullock, 
Architect and Editor of "The Rudiments of Architecture and- 
Building," etc., etc. Illustrated by, 75 engravings. 8vo. SS-S© 

BULLOCK. — The Rudiments of Architecture and Building: 
For the use of Architects, Builders, Draughtsmen, Machinists, En- 
gineers and Mechanics. Edited by John Bullock, author of " The 
American Cottage Builder." Illustrated by 250 Engravings. Svo. ;^3.50 



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BURGH. — Practical Rules for the Proportions of Modern 
Engines and Boilers for Land and Marine Purposes. 

By N. P. Burgh, Engineer. i2mo. .... $1.50 

BURNS. — The American Woolen Manufacturer: 

A Practical Treatise on the Manufacture of Woolens, in two parts. 
Part First gives full and explicit instructions upon Drafting, Cross- 
Drawing, Combining Weaves, and the correct arrangement of Weights, 
Colors and Sizes of Yarns to produce any desired fabric. Illustrated 
with diagrams of various weavings, and twelve samples of cloth for 
explanation and practice. Part Second is fully supplied with ex- 
tended Tables, Rules, Examples, Explanations, etc. ; gives full and 
practical information, in detailed order, from the stock department to 
the market, of the proper selection and use of the various grades and 
staples of wool, with the admixture of waste, cotton and shoddy; and 
the proper application and economical use of the various oils, drugs, 
dye stuffs, soaps, belting, etc. Also, the most approved method for 
Calculating and Estimating the Cost of Goods, for all Wool, Wool 
Waste and Cotton and Cotton Warps. With Examples and Calcula- 
tions on the Circular motions of Wheels, Pinions, Drums, Pulleys 
and Gears, how to speed them, etc. The two parts combined form a 
whole work on the American way of manufacturing more complete 
than any yet issued. Ey George C. Burns. 8vo. . . ^6.50 

BYLES.— Sophisms of Free Trade and Popular Political 

Economy Examined. 

By a Barrister (Sir John Barnard Byles, Judge of Common 

Pleas). From the Ninth English Edition, as published by the 

Manchester Reciprocity Association. lamo. . , . ^1.25 

BYRN. — The Complete Practical Brewer: 

Or Plain, Accurate and Thorough Instructions in the Art of Brewing 
Beer, Ale, Porter, including the Process of Making Bavarian Beer, 
all the Small Beers, such as Root-beer, Ginger-pop, Sarsaparilla-beer, 
Mead, Spruce Beer, etc. Adapted to the use of Puolic Brewers and 
Private Families. By M. La Fayette Byrn, M. D. With illus- 
trations. i2mo. ........ 

BYRN.— The Complete Practical Distiller: 

Comprising the most perfect and exact Theoretical and Practical De- 
scription of the Art of Distillation and Rectification; including all of 
the most recent improvements in distilling apparatus; instructions for 
preparing spirits from the numerous vegetables, fruits, etc ; directions 
for the distillation and preparation of all kinds of brandies and other 
spirits, spirituous and other compounds, etc. By M. La Fayette 
Byrn, M. D. Eighth Edition. To which are added Piactical 
Directions for Distilling, from the French of Th. Fling, Brewer and 
Distiller. l2mo • . . ^1.50 

BYRNE. — Hand-Book for the Artisan, Mechanic, and Engi- 
neer: 
Comprising the Grinding and Sharpening of Cutting Tools, Abrasive 
Processes, Lapidary Work, Gem and Glass Engraving, Varnishing 
and Lackering, Apparatus, Materials and Processes for Grinding and 



HENRY CAREY BAIRD & CO.'S CATALOGUE. 



Polishing, etc. By Oliver Byrne. Illustrated by 185 wood en- 
gravings. 8vo. ........ ^5.00 

BYRNE. — Pocket-Book for Railroad and Civil Engineers : 

Containing New, Exact and Concise Methods for I^aying out Railroad 
Curves, Switches, Frog Angles and Crossings ; the Staking out of 
work ; Levelling ; the Calculation of Cuttings ; Embankments ; Earth- 
work, etc. By Oliver Byrne. i8mo., full bound, pocket-book 
form ^1-75 

BYRNE. — The Practical Metal- Worker's Assistant : 

Comprising Metallurgic Chemistry ; the Arts of Working all Metals 
and Alloys; Forging of Iron and Steel; Hardening and Tempering; 
Melting and Mixing; Casting and Founding ; Works in Sheet Metal; 
the Processes Dependent on the Ductility of the Metals; Soldering; 
and the most Improved Processes and Tools employed by Metal- 
workers. With the Application of the Art of Electro-Metaliurgy to 
Manufacturing Processes ; collected from Original Sources, and from 
the works of Holtzapffel, Bergeron, Leupold, Plunfiier, Napier, 
Scoffern, Clay, Fairbairn and others. By OLIVER Byrne. A new, 
revised and improved edition, to which is added an Appendix, con- 
taining The Manufacture of Russian Sheet-Iron, By John Percy, 
M. D., F. R. S. The Manufacture of Malleable Iron Castings, and 
Improvements in Bessemer Steel. By A. A. Fesquet, Chemist and 
Engineer. With over Six Hundred Engravings, Illustrating every 
Branch of the Subject. Svo ^y.oc 

BYRNE.— The Practical Model Calculator : 

For the Engineer, Mechanic, Manufacturer of Engine Work, Naval 
Architect, Miner and Millwright. By Oliver Byrne. 8vo., nearly 
600 pages ......... ^4.50 

CABINET MAKER'S ALBUM OF FURNITURE: 

Comprising a Collection of Designs for various Styles of Furniture. 
Illustrated by Forty-eight Large and Beautifully Engraved Plates. 
Oblong, Svo #3.50 

CALLINGHAM. — Sign W^riting &nd Glass Embossing: 

A Complete Practical Illustrated Manual of the Art. By James 
Callingham. i2mo ^1.50 

CAMPIN. — A Practical Treatise on Mechanical Engineering: 
Comprising Metallurgy, Moulding, Casting, Forging, Tools, Work, 
shop Machinery, Mechanical Manipulation, Manufacture of Steam- 
Engines, etc. With an Appendix on the Analysis of Iron and Iron 
Ores. By Francis Campin, C. E. To which are added. Observations 
on the Construction of Steam Boilers, and Remarks upon Furnaces 
used for Smoke Prevention ; with a Chapter on Explosions. By R. 
Armstrong, C. E., and John Bourne. Rules for Calculating the 
Change Wheels for Screws on a Turning Lathe, and for a Wheel- 
cutting Machine. By J. La Nicca. Management of Steel, Includ- 
ing Forging, Hardening, Tempering, Annealing, Shrinking and 
Expansiiin ; and the Case-hardening of Iron. By G. Ede. Svo. 
Illustrated with twenty-nine plates and lOO wood engravings $S-Oo 



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CAREY.— A Memoir of Henry C. Carey. 

By Dr. Wm. Elder. With a portrait. 8vo., cloth . -75 

CAREY.— The Works of Henry C. Carey : 

Harmony of Interests : Agricultural, Manufacturing and Commer- 
cial. 8vo. ........ ^1.50 

Manual of Social Science. Condensed from Carey's " Principles 
of Social Science." By Kate McKean. i vol. i2mo. . ^2.25 
Miscellaneous Works. With a Portrait. 2 vols. 8vo. $6.00 

Past, Present and Future. Svo , ^2.50 

Principles of Social Science. 3 volumes, Svo. . . ^lo.oo 
The Slave-Trade, Domestic and Foreign; Why it Exists, and 
How it may be Extinguished (1853). Svo. . . . ^2.00 

The Unity of Law : As Exhibited in the Relations of Physical, 
Social, Mental and Moral Science (1872). Svo. . . fc.50 

CLARK. — Tramways, their Construction and Working : 

Embracing a Comprehensive History of the System. With an ex- 
haustive analysis of the various modes of traction, including horse- 
power, steam, heated water and compressed air; a description of the 
varieties of Rolling stock, and ample details of cost and working ex- 
penses. By D. KiNNEAR Clark. Illustrated by over 200 wood 
engravings, and thirteen folding plates. 2 vols. Svo. . ^12.50 

COLBURN.— The Locomotive Engine : 

Including a Description of its Structure, Rules for Estimating its 
Capabilities, and Practical Observations on its Construction and Man- 
agement. By Zerah CoLBURN. Illustrated. i2mo. . ^i.oo 

COLLENS.— The Eden of Labor; or, the Christian Utopia. 
By T. Wharton Collens, author of " Humanics," " The History 
of Charity," etc. i2mo. Paper cover, ^i. 00; Cloth . ^1.25 

COOLEY. — A Complete Practical Treatise on Perfumery : 

Being a Hand-book of Perfumes, Cosmetics and other Toilet Articles, 
With a Comprehensive Collection of Formulae. By Arnold J. 
CoOLEY. l2mo. . . . . . . . . ^1.50 

COOPER.— A Treatise on the use of Belting for the Trans- 
mission of Power. 
With numerous illustrations of approved and actual methods of ar- 
ranging Main Driving and Quarter Twist Belts, and of Belt Fasten- 
ings. Examples and Rules in great number for exhibiting and cal- 
culating the size and driving power of Belts. Plain, Particular and 
Practical Directions for the Treatment, Care and Management of 
Belts. Descriptions of many varieties of Beltings, together with 
chapters on the Transmission of Power by Ropes ; by Iron and 
Wood Frictional Gearing; on the Strength of Belting Leather; and 
on the Experimental Investigations of Morin, Briggs, and others. By 
John H. Cooi'er, M. E. Svo ^3.50 

CRAIK. — The Practical American Millwright and Miller. 

By David Craik, Millwright. Illustrated by numerous wood en- 
■ gravings and two folding plates. Svo. . . . . $S-00 



HENRY CAREY BAIRD & CO.'S CATALOGUE. 



CRISTIANI. — A Technical Treatise on Soap and Candles: 

. With a Glance at the Industry of Fats and Oils. By R. S. Cris- 
TIANI, Chemist. Author of " Perfumery and Kindred Arts." Illus- 
trated by 176 engravings. 581 pages, 8vo. . . . ^7.50 

CRISTIANI. — Perfumery and Kindred Arts : 

A Comprehensive Treatise on Perfumery, containing a History of 
Perfumes from the remotest ages to the present time. A complete 
detailed description of the various Materials and Apparatus used in 
the Perfumer's Art, with thorough Practical Instruction and careful 
Formulae, and advice for the fabrication of all known preparations of 
the day, including Essences, Tinctures, Extracts, Spirits, Waters, 
Vinegars, Pomades, Powders, Paints, Oils, Emulsions, Cosmetics, 
Infusions, Pastilles, Tooth Powders and Washes, Cachous, Hair Dyes, 
Sachets, Essential Oils, Flavoring Extracts, etc. ; and full details for 
, making and manipulating Fancy Toilet Soaps, Shaving Creams, etc., 
by new and improved methods. With an Appendix giving hints and 
advice for making and fermenting Domestic Wines, Cordials, Liquors, 
Candies, Jellies, Syrups, Colors, etc., and for Perfuming and Flavor- 
ing Segars, Snuff and Tobacco, and Miscellaneous Receipts for 
various useful Analogous Articles. By R. S. Cristiani, Con- 
sulting Chemist and Perfumer, Philadelphia. 8vo. . . ^5-00 

CUPPER.— The Universal Stair-Builder : 

Being a new Treatise on the Construction of Stair-Cases and Hand- 
Rails; showing Plans of the various forms of Stairs, method of 
Placing the Risers in the Cylinders, general method of describing 
the Face Moulds for a Hand-Rail, and an expeditious method of 
Squaring the Rail. Useful also to Stonemasons constructing Stone 
Stairs and Hand-Rails ; with a new method of Sawing the Twist 
Part of any Hand-Rail square from the face of the plank, and to a 
parallel width. Also, a new method of forming the Easings of the 
Rail by a gauge ; preceded by some necessary Problems in Practical 
Geometry, with the Sections of Prismatic Solids. Illustrated by 29 
plates. By R. A. Cupper, Architect, author of " The Practical 
Stair-Builder's Guide." Third Edition. Large 4to. . ^2.50 

DAVIDSON.— A Practical Manual of House Painting, Grain- 
ing, Marbling, and Sign- Writing : 
Containing full information on the processes of House Painting in 
Oil and Distemper, the Formation of Letters and Practice of Sign- 
Writing, the Principles of Decorative Art, a Course of Elementary 
Drawing for House Painters, Writers, etc., and a Collection of Useful 
Receipts. With nine colored illustrations of Woods and Marbles, 
and numerous wood ejigravings. By Ellis A. Davidson. i2mo. 

fe-oo 

DAVIES. — A Treatise on Earthy and Other Minerals and 
Mining : 
By D. C. Davies, F. G. S., Mining Engineer, etc. Illustrated by 
76 Engravings. i2mo $S-°^ 



to HENRY CAREY BAIRD & CO.'S CATALOGUE. 

DAVIES. — A Treatise on Metalliferous Minerals and Mining: 
By D. C. Davies, F. G. S., Mining Engineer, Examiner of Mines, 
Quarries and Collieries. Illustrated by 14S engravings of Geological 
Formations, Mining Operations and Machinery, drawn from th* 
practice of all parts of the world. 2d Edition, i2mo., 450 pages ^5.00 

DAVIES.— A Treatise on Slate and Slate Quarrying: 

Scientific, Practical and Commercial. By D. C. Davies, F. G. S., 
Mining Engineer, etc. With numerous illustrations and folding 
plates. i2mo. . . . . . . . . ^2.50 

DAVIS. — A Practical Treatise on the Manufacture of Bricks, 
Tiles, Terra-Cotta, etc. : 

Including Common, Pressed, Ornamentally Shaped, and Enamelled 
Bricks, Drain-Tiles, Straight and Curved Sewer-Pipes, Fire-Clays, 
Fire-Bricks, Terra-Cotta, Roofing-Tiles, Flooring-Tiles, Art-Tiles, 
Mosaic Plates, and Imitation of Intarsia or Inlaid Surfaces; com- 
prising every important Product of Clay employed in Architecture, 
Engineering, the Blast-Furnace, for Retorts, etc., with a History and 
the Actual Processes in Handling, Disintegrating, Tempering, and 
Moulding the Clay into Shape, Drying Naturally and Artificially, 
Setting and Burning, Enamelling in Polychrome Colors, Composition 
and Application of Glazes, etc. ; including Full Detailed Descriptions 
of the most modern Machines, Tools, Kilns, and Kiln-Roofs used. 
By Charles Thomas Davis. Illustrated by 228 Engravings and 

6 Plates. 8vo., 472 pages ^S-OO 

DAVIS. — The Manufacture of Leather: 

Being a description of all of the Processes for the Tanning, Currying, 

and Finishing of Leather ; including the Various Raw Materials and 

the Methods for Determining their Values; the Tools, Machines, 

and all Matters of Importance connected with an Intelligent and 

Profitable Prosecution of the Art, with Special Reference to the best 

American Practice. To which is added a List of American Patents 

for Materials, Processes, Tools and Machines for Tanning, Currying, 

etc. By Charles T. Davis. Illustrated by about 300 engravings. 

In one volume, 8vo., of about 850 pages. [In pirss.) 

DAWIDOWSKY— BRANNT.— A Practical Treatise on the 

Raw Materials and Fabrication of Glue, Gelatine, Gelatine 

Veneers and Foils, Isinglass, Cements, Pastes, Mucilages, 

etc. : 

Eased upon Actual Experience. By F. Dawidowsky, Technical 

Chemist. Translated from the German, with extensive additions, 

including a description of the most Recent American Processes, by 

William T. Brannt, Graduate of the Royal Agricultural College 

of Eldena, Prussia. 35 Engravings. l2mo. . . , ^^2.50 

DE GRAFF.— The Geometrical Stair-Builders' Guide: 

Being a Plain Practical System of Hand-Railing, embracing all its 
necessary Details, and Geometrically Illustrated by twenty-two Steel 
Engravings ; together with the use of the most approved principles 
of Practical Geometry. By Simon De Graff, Architect. 4to. 

^2.50 



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DE KONINCK— DIETZ.— A Practical Manual of Chemical 
Analysis and Assaying : 

As applied to the Manufacture of Iron from its Ores, and to Cast Iron, 
Wrought Iron, and Steel, as found in Commerce. By L. L. De 
KoNiNCK, Dr. Sc, and E. Dietz, Engineer. Edited with Notes, by 
Robert Mallet, F. R. S., F. S. G., M. I. C. E., etc. American 
Edition, Edited with Notes and an Appendix on Iron Ores, by A. A. 
Fesquet, Chemist and Engineer. i2mo. . . . ,^2.50 

DUNCAN. — Practical Surveyor's Guide: 

Containing the necessary information to make any person of com- 
mon capacity, a finished land surveyor without the aid of a teacher. 
By Andrew Duncan. Illustrated. i2mo. . . . #1.25 

DUPLAIS. — A Treatise on the Manufacture and Distillation 
of Alcoholic Liquors : 
Comprising Accurate and Complete Details in Regard to Alcohol 
from Wine, Molasses, Beets, Grain, Rice, Potatoes, Sorghum, Aspho- 
del, Fruits, etc. ; with the Distillation and Rectification of Brandy. 
Whiskey, Rum, Gin, Swiss Absinthe, etc., the Preparation of Aro- 
matic Waters, Volatile Oils or Essences, Sugars, Syrups, Aromatic 
Tinctures, Liqueurs, Cordial Wines, Effervescing Wines, etc., the 
Ageing of Brandy and the improvement of Spirits, with Copious 
Directions and Tables for Testing and Reducing S]:iirituous Liquors, 
etc., etc. Translated and Edited from the French of MM. Dupi.ais, 
Aine et Jeune. By M. McKennie, M. D. To which are added the 
United States Internal Revenue Regulations for the Assessment and 
Collection of Taxes on Distilled Spirits. Illustrated by fourteen 
folding plates and several wood engravings. 743 pp. 8vo. ^1000 

DUSSAUCE. — A General Treatise on the Manufacture of 
Vinegar: 
Theoretical and Practical. Comprising the various Methods, by the 
Slow and the Quick Processes, with Alcohol, Wine, Grain, Malt, 
Cider, Molasses, and Beets ; as well as the Fabrication of Wood 
Vinegar, etc., etc. By Prof. H. DussAUCE. 8vo. . ^5 00 

DUSSAUCE.— Practical Treatise on the Fabrication of Matches, 
Gun Cotton, and Fulminating Powder. 
By Professor H. Dussauce. i2mo. . . . . $3 00 

DYER AND COLOR-MAKER'S COMPANION: 

Containing upwards of two hundred Receipts for making Colors, on 
the most approved principles, for all the various styles and fabrics now 
in existence; with the Scouring Process, and plain Directions for 
Preparing, Washing-off, and Finishing the Goods. l2mo. ^i 25 

EDWARDS. — A Catechism of the Marine Steam-Engine, 
For the use of Engineers, Firemen, and Mechanics. A Practical 
Work for Practical Men. By Emory Edwards, Mechanical Engi- 
neer. Illustrated by sixty-three Engravings, including examples of 
the most modern Engines. Third edition, thoroughly revised, with 
much additional matter. l2mo. 414 pages . . . ^2 00 

EDWARDS. — Modern American Locomotive Engines, 

Their Design, Construction and Management. By Emory Edwards. 
Illustrated i2mo $2 00 



12 HENRY CAREY BAIRD & CO.'S CATALOGUE;. 

EDWARDS. — Modern American Marine Engines, Boilers, and 
Screw Propellers, 

Their Design and Construction. Showing the Present Practice of 
the most Eminent Engineers and Marine Engine Builders in the 
United States. lUustrated by 30 large and elaborate plates. 4to. ^5.00 

EDWARDS.— The Practical Steam Engineer's Guide 

In the Design, Construction, and Management of American Stationary, 
Portable, and Steam Fire-Engines, Steam Pumps, Boilers, Injectors, 
Governors, Indicators, Pistons and Rings, Safety Valves and Steam 
Gauges. For the use of Engineers, Firemen, and Steam Users. By 
Emory Edwards. Illustrated by 119 engravings. 420 pages. 
l2mo. .......... ^2 50 

ELDER.— Conversations on the Principal Subjects of Political 
Economy. 
By Dr. William Elder. 8vo. ^2 50 

ELDER.— Questions of the Day, 

Economic and Social. By Dr. William Elder. 8vo. . ^3 00 

ELDER. — Memoir of Henry C. Carey. 

By Dr. William Elder. 8vo. cloth 75 

ERNI. — Mineralogy Simplified. 

Easy Methods of Determining and Classifying Minerals, including 
Ores, by means of the Bio\v]iipe, and by Humid Chemical Analysis, 
based on Professor von Kobell's Tables for the Determination of 
Minerals, with an Introduction to Modern Chemistry. By Henry 
Erni, A.m., M.D., Professor of Chemistry. Second Edition, rewritten, 
enlarged and improved. i2mo. (^J7i press.) 

FAIRBAIRN.— The Prmciples of Mechanism and Machinery 
of Transmission • 
Comprising the Prmciples of Mechanism, Wheels, and Pulleys, 
Strength and Proportions of Shafts, Coupling of Shafts, and Engag- 
ing and Disengaging Gear. By SiR William Fairbairn, Bait. 
C. E. Beautifully illustrated by over 150 wood-cuts. In one 
volume, i2mo ......... ^2.50 

FITCH.— Bessemer Steel, 

Ores and Methods, New Facts and Statistics Relating to the Types 
of Machinery in Use, the Methods in Vogue, Cost and Class of Labor 
employed, and the Character and Availability of the Ores utilized in 
the Manufacture of Bessemer Steel in Europe and in the United States ; 
togetherwith opinions and excerpts from various accepted authorities. 
Compiled and arranged by Thomas W. Fitch. 8vo. . ^3 00 

FLEMING. — Narrow Gauge Railways in America. 

A Sketch of their Rise, Progress, and Success. Valuable Statistics 
as to Grades, Curves, Weight of Rail, Locomotives, Cars, etc. By 
Howard Fleming. Illustrated, Svo. . . . . $1 50 

FORSYTH.— Book of Designs for Headstones, Mural, and 
other Monuments : 
Containing 78 Designs. By James Forsyth. With an Introduction 
by Charles Boutell, M. A. 4 to., cloth . . . $5 00 



HENRY CAREY BAIRD & CO.'S CATALOGUE. 13 



FRANKEL— HUTTER.— A Practical Treatise on the Manu- 
facture of Starch, Glucose, Starch-Sugar, and Dextrine : 

Based on the German of Ladislaus Vox Wagner, Professor in the 
Royal Technical High School, Buda-Pest, Hungary, and oiher 
aiithorities. By Julius Frankel, Graduate of the Polytechnic 
School of Hanover. Edited by Robert Hutter, Chemist Practical 
Manufacturer of Starch-Sugar. Illustrated by 58 engravings, cover- 
ing every branch of the subject, including examples of "the most 
Recent and Best American Machinery. 8vo., 344 pp. . ^3.50 

GEE.— The Goldsmith's Handbook : 

Containing full instructions for the Alloying and Working of Gold 
including the Art of Alloying, Melting, Reducing, Coloring, Col- 
lecting, and Refining; the Processes of Manipulation, Recovery of 
Waste; Chemical and Physical Jroperlies of Gold; with a New 
System of Mixing its Alloys; Solders, Enamels, and other Useful 
Rules and Recipes. By George E. Gee. i2mo. . . ;^i.75 

GEE.— The Silversmith's Handbook : 

Containing full instructions for the Alloying and Working of Silver, 
including the different modes of Refining and Melting thtTMetal; its 
Solders; the Preparation of Imitation Alloys; Methods of Manipula- 
tion; Prevention of Waste; Instructions for Improving and Finishing 
the Surface of the Work; together with other Useful InfoiTnation and 
Memoranda. By George E. Gee, Jeweller. Illustrated. i2mo. 

GOTHIC ALBUM FOR CABINET-MAKERS : ^'^^ 

Designs for Gothic Furniture. Twenty-three plates. Oblong ;g2.oo 
GREENWOOD.— Steel and Iron: 

Comprising the Practice and Theory of the Several Methods Pur- 
sued in their Manufacture, and of their Treatment in the Rolling- 
Mills, the Forge, and the Foundry. By William Henry Green- 
wood, F. C. S. Asso. M. I. C. E., M. I. M. E., Associate of the Royal 
School of Mines. With 97 Diagrams, 536 pages. i2mo. . ^2.00 
GREGORY.— Mathematics for Practical Men : 

Adapted to the Pursuits of Sui-veyors, Architects, Mechanics, and 
Civd Engineers. By Olinthus Gregory. 8vo., plates . S^ 00 
GRIER.— Rural Hydraulics : ' f Pd- 

A Practical Treatise on Rural Household Water Supply. Giving a 
full description of Springs and Wells, of Pumps and Hydraulic Ram 
with Instructions in Cistern Building, Laying of Pipes, etc By w' 
W. Grier. Illustrated 8vo. -- 

GRIMSHAW.— Modern Milling: • • • • /5 

Being the substance of two addresses delivered by request, at the 
Frankkn Institute, Philadelphia, January 19th and January 27th 
1 88 1. By Robert Grimshaw, Ph. D. Edited from the Phono- 
graphic Reports. With 28 Illustrations. 8vo. *i 00 
GRIMSHAW.— Saws : * 
The History, Development, Action, Classification, and Comparison 
of Saws of all kinds. IVM Copious Appendices. Giving the details 



14 HENRY CAREY BAIRD & CO.'S CATALOGUE. 

of Manufacture, Filing, Setting, Gumming, etc. Care and Use of 
Saws; Tables of Gauges; Capacities of Saw-Mills; List of Saw- 
Patents, and other valuable information. By Robert Grimshaw. 
Second and greatly enlarged edition, with Supplement, and 354 Illus- 
trations. Quarto $4.00 

GRIMSHAW. — A Supplement to Grimshaw on Saws: 

Containing additional practical matter, more especially relating to the 
Forms of Saw-Teeth, for special material and conditions, and to the 
Behavior of Saws under particular conditions. 120 Illustrations. By 
Robert Grimshaw. Quarto ^2.00 

GRISWOLD. — Railroad Engineer's Pocket Companion for the 
Field : 
Comprising Rules for Calculating Deflection Distances and Angles, 
Tangential Distances and Angles, and all Necessary Tables for En- 
■ gineers; also the Art of Levelling from Preliminary Survey to the 
Construction of Railroads, intended Expressly for the Young En- 
gineer, together with Numerous Valuable Rules and Examples. By 
W. Griswold. i2mo., tucks ^1-75 

GRvJNER. — Studies of Blast Furnace Phenomena: 

By M. L. Gruner, President of the General Council of Mines of 
France, and lately Professor of Metallurgy at the Ecole des Mines. 
Translated, with the author's sanction, with an Appendix, by L. D. 
B. Gordon, F. R. S. E., F. G. S. 8vo. . . . ^2.50 

GUETTIER.— Metallic Alloys: 

Being a Practical Guide to their Chemical and Physical Properties, 
their Preparation, Composition, and Uses. Translated from the 
French of A. GUETTIER, Engineer and Director of Founderies, 
author of " La Fouderie en France," etc., etc. By A. A. Fesquet, 
Chemist and Engineer, i2mo. ..... $3.00 

HASERICK.— The Secrets of the Art of Dyeing Wool, Cotton, 
and Linen, 
Including Bleaching and Coloring Wool and Cotton Hosiery and 
Random Yarns. A Treatise based on Economy and Practice. By 
E. C. Haserick. Illustrated by 323 Dyed Patterns of the Yarns 
or Fabrics. 8vo. ........ $2.^.<Xi 

HATS AND FELTING: 

A Practical Treatise on their Manufacture. By a Practical Hatter, 
Illustrated by Drawings of Machinery, etc. 8vo. . . ^1.25 

HENRY. — The Early and Later History of Petroleum : 

With Authentic Facts in reeard to its Development in Western Penn- 
sylvania. With Sketches of the Pioneer and Prominent Operators, 
together with the Refining Capacity of the United States. By J. T. 
Henry. Illustrated 8vo. ^4.50 

HOFFER. — A Practical Treatise on Caoutchouc and Gutta 

Percha, 

Comprising the Properties of the Raw Materials, and the manner of 

Mixing and Working them ; with the Fabrication of Vulcanized and 

Hard Rubbers, Caoutchouc and Gutta Percha Compositions, Water- 



HENRY CAREY BAIRD & CO.'S CATALOGUE. 15 

proof Substances, Elastic Tissues, the Utilization of Waste, etc., etc. 
From the German of Raimund Hoffer. By W. T. Erannt. 
Illustrated i2mo. ........ (^2.50 

HOFMANN.— A Practical Treatise on the Manufacture of 
Paper in all its Branches : 
By Carl Hofmann, I.ate Superintendent of Paper-Mills in Germany 
and the United States; recently Manager of the "Public Ledger" 
Paper-Mills, near Elkton, Maryland. Illustrated by no wood en- 
gravings, and five large Folding Plates. 4to., cloth; about 400 
pages ^30.00 

HUGHES. — American Miller and Millwright's Assistant : 
By William Carter Hughes. i2mo $1.50 

HULME. — Worked Examination Questions in Plane Geomet- 
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For the Use of Candidates for the Royal Military Academy, Wool- 
wich ; the Royal Military College, Sandhurst ; the Indian Civil En- 
gineering College, Cooper's Hill ; Indian Public Works and Tele- 
graph Departments ; Royal Marine Light Infantry ; the Oxford and 
Cambridge Local Examinations, etc. By F. Edward Hulme, F. L. 
S., F. S. A., Art-Master Marlborough College. Illustrated by 300 
examples. Small quarto $3-7S 

JERVIS.— Railroad Property: 

A Treatise on the Construction and Management of Railways; 
designed to afford useful knowledge, in the popular style, to the 
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cers, and Agents. By John B. Jervis, late Civil Engineer of the 
Hudson River Railroad, Croton Aqueduct, etc. i2mo., cloth ^2.00 

KEENE.— A Hand-Book of Practical Gauging: 

For the Use of Beginners, to which is added a Chapter on Distilla- 
tion, describing the process in operation at the Custom-House for 
ascertaining the Strength of Wines. By James B. Keene, of H. M. 
Customs. 8vo. ........ $1-25 

KELLEY. — Speeches, Addresses, and Letters on Industrial and 
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By Hon. William D. Kelley, M. C. 544 pages, 8vo. . $3.00 

KELLOGG. — A New Monetary System ; 

The only means of Securing the respective Rights of Labor and 
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By Edward Kellogg. Revised from his work on "Labor and 
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Edited by MARY Kellogg Putnam. Fifth edition. To which is 
added a Biographical Sketch of the Author. One volume, l2mo. 

Paper cover . . $i.oa 

Bound in cloth 1. 50 

KEMLO.— Watch-Repairer's Hand-Book : 

Being a Complete Guide to the Young Beginner, in Taking Apart, 
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other Foreign Watches, and all American Watches. By F. Kemlo, 
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l6 HENRY CAREY BAIRD & CO.'S CATALOGUE. 

KENTISH. — A Treatise on a Box of Instruments, 

And the Slide Rule ; with the Theory of Trigonometry and Loga- 
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ber, Cask and Malt Gauging, Heights, and Distances. By Thomas 
Kentish. In one volume. i2mo. . . . . ^1.25 

KERL.— The Assayer's Manual: 

An Abridged Treatise on the Docimastic Examination of Ores, and 
Furnace and other Artificial Products. By Bruno Kerl, Professor 
in the Royal School of Mines ; Member of the Royal Technical 
Commission for the Industries, and of the Imperial Patent-Ofifice, 
Berlin. Translated from the German by William T. Brannt, 
Graduate of the Royal Agricultural College of Eldena, Prussia. 
Edited by William H..Wahl, Ph. D., Secretary of the Franklin 
Institute, Piuiadelphia. Illustrated by sixty-five engravings. 8vo. 

^3.00 

KINGZETT. — The History, Products, and Processes of the 
Alkali Trade : 
Including the most Recent Improvements. By Charles Thomas 
KiNGZETT, Consulting Chemist. With 23 illustrations. 8vo. 12.5a 

KINSLEY. — Self-Instructor on Lumber Surveying: 

For the Use of Lumber Manufacturers, Surveyors, and Teachers. 
By Charles Kinsley, Practical Surveyor and Teacher of Surveying. 
l2mo ^2.00 

KIRK. — The Founding of Metals : 

A Practical Treatise on the Melting of Iron, with a Description of the 
Founding of Alloys; also, of all the Metals and Mineral Substances 
used in the Art of Founding. Collected from original sources. By 
Edward Kirk, Practical Foundryman and Chemist. Illustrated. 
Third edition. 8vo . ^2.50 

KITTREDGE.— The Compendium of Architectural Sheet- 
Metal Work : 
Profusely Illustrated. Embracing Rules and Directions for Estimates, 
Items of Cost, Nomenclature, Tables of Brackets, Modillions, Den- 
tals, Trusses, Stop-Blocks, Frieze Pieces, etc. Architect's Specifica- 
tion, Tables of Tin-Roofing, Galvanized Iron, etc., etc. To which is 
added the Exemplar of Architectural Sheet-Metal Work, containing 
details of the Centennial Buildings, and other important Sheet-Metal 
Work, Designs and Prices of Architectural Ornaments, as manufac- 
tured for the Trade by the Kittredge Cornice and Ornament Com- 
pany, and a Catalogue of Cornices, Window-Caps, Mouldings, etc., as 
manufactured by the Kittredge Cornice and Ornament Company. 
The whole supplemented by a full Index and Table of Contents. By 
A. O. Kittredge. 8vo., 565 pages .... ^5.00 

t-ANDRIN.— A Treatise on Steel: 

Comprising its Theory, Metallurgy, Properties, Practical Working, 
and Use. By M. H. C. Landrin,'Jr., Civil Engineer. Translated 
from the French, with Notes, by A. A. Fesquet, Chemist and En- 
gineer. With an Appendix on the Bessemer and the Martin Pre 
cesses for Manufacturing Steel, from the Report of Abram S. Hewitt 



HENRY CAREY BAIRD & CO.'S CATALOGUE. 17 

United States Commissioner to the Jniversal Exposition, Paris, 1867. 

■ l2mo ^3.00 

LARDEN.— A School Course on Heat: 

By W. Larden, M. A. 321 pp. i2mo. .... I2.00 
LARDNER.— The Steam-Engine: 

For the Use of Beginners. By Ur. Lardner. Illustrated. i2mo. 

75 
LARKIN. — The Practical Brass and Iron Founder's Guide : 

A Concise Treatise on Brass Founding, Moulding, the Metals and 

their Alloys, etc.; to which are added Recent Improvements in the 

Manufacture of Iron, Steel by the Bessemer Process, etc., etc. By 

James Larkin, late Conductor of the Brass Foundry Department iu 

Reany, Neafie & Co.'s Penn Works, Philadelphia. Fifth edition, 

revised, with extensive additions. i2mo. . . . ^2.25 

I.EROUX.— A Practical Treatise on the Manufacture of 
Worsteds and Carded Yarns : 
Comprising Practical Mechanics, wi'th Rules and Calculations applied 
to Spinning; Sorting, Cleaning, and Scouring Wools; the English 
and French Methods of Combing, Drawing, and Spinning Worsteds, 
and Manufacturing Carded Yarns. Translated from the French of 
Charles Leroux, Mechanical Engineer and Superintendent of a 
Spinning-Mill, by Horatio Paine, M. D., and A. A. Fesquet, 
Chemist and Engineer. Illustrated by twelve large Plates. To which 
is added an Appendix, containing Extracts from the Reports of the 
International Jury, and of the Artisans selected by the Conmiittee 
appointed by the Council of the Society of Arts, London, on Woolen 
and Worsted Machinery and Fabrics, as exhibited in the Paris Uni- 
versa! Exposition, 1867. 8vo. ..... ^5.00 

LEFFEL.— The Construction of Mill-Dams : 

Comprising also the Building of Race and Reservoir Embankments 
and Head-Gates, the Measurement of Streams, Gauging of Water 
Supply, etc. By James Leffel & Co. Illustrated by 58 engravings. 
8vo ^2,50 

LESLIE.— Complete Cookery: 

Directions for Cookery in its Various Branches. By Miss Leslie, 
Sixtieth thoasand. Thoroughly revised, with the addition of New 
Receipts. In i2mo., cloth #1.50 

LIEBER.— Assayer's Guide : 

Or, Practical Directions to Assayers, Miners, and Smelters, for the 
Tests and Assays, by Heat and by Wet Processes, for the Ores of all 
the principal Metals, of Gold and Silver Coins and Alloys, and of 
Coal, etc. By OscAR M. Lieber. i2nio. . . . ^1.25 

LOVE. — The Art of Dyeing, Cleaning, Scouring, and Finish- 
ing, on the Most Approved English and French Methods : 
Being Practical Instructions in Dyeing Silks, Woolens, and Cottons, 
Feathers, Chips, Straw, etc. Scouring and Cleaning Bed and Win- 
dow Curtains, Carpets, Rugs, etc. French and English Cleaning, 
any Color or Fabric of Silk, Satin, or Damask. By Thomas Love, 
a Working Dyer and Scourer. Second American Edition, to which 



l8 HENRY CAREY BAIRD & CO.'S CATALOGUE. 

are added General Instructions for the use of Aniline Colors. 8vo. 

343 pages ^5.00 

LUKIN. — Amongst Machines; 

Embracing Descriptions of the various Mechanical Appliances used 
in the Manufacture of Wood, Metai, and other Substances. lamo. 

^1-75 
LUKIN.— The Boy Engineers : 

What They Did, and How They Did It. With 30 plates. iSmo. 

^1-75 
LUKIN.— The Young Mechanic : 

Practical Carpentry. Containing Directions for the Use of all kinds 

of Tools, and for Construction of Steam-Engines and Mechanical 

Models, including the Art of Turning in Wood and Metal. By John 

LuKiN, Author of "The Lathe and Its Uses," etc. Illustrated. 

l2mo $1-75 

MAIN and BROWN. — Questions on Subjects Connected with 

the Marine Steam-Engine ; 

And Examination Papers; with Hints for their Solution, By 

Thomas J. Main, Professor of Mathematics, Royal Naval College, 

and Thomas Brown, Chief Engineer, R. N. i2mo., cloth . ^1.50 

MAIN and BROWN. — The Indicator and Dynamometer : 
With their Practical Applications to the Steam-Engine. By Thomas 
J. Main, M. A. F. R., Ass't S. Professor Royal Naval College, 
Portsmouth, and Thomas Brown, Assoc. Inst. C. E., Chief Engineer 
R. N., attached to the R. N. College. Illustrated. 8vo. . ^1.50 

MAIN and BROWN.— The Marine Steam-Engine. 

By Thomas J. Main, F. R. Ass't S. Mathematical Professor at the 
Royal Naval College, Portsmouth, and Thomas Brown, Assoc. 
Inst. C. E., Chief Engineer R. N. Attached to the Royal Naval 
College. With numerous illustrations. 8vo. . . . i^S-OO 

MARTIN.— Screw-Cutting Tables, for the Use of Mechanical 
Engineers : 
Showing the Proper Arrangement of Wheels for Cutting the Threads 
of Screws of any Required Pitch ; with a Table for Making the Uni- 
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8vo. 50 

MICHELL.— Mine Drainage: 

Being a Complete and Practical Treatise on Direct-Acting Under- 
ground Steam Pumping Machinery. With a Description of a large 
number of the best known Engines, their General Utility and the 
Special Sphere of their Action, the Mode of their Application, and 
their Merits compared with other Pumping Machinery. By Stephen 
MiCHELL. Illustrated by 137 engravings. 8vo., 277 pages . ^6.00 

MOLESWORTH.— Pocket-Book of Useful Formulae and 
Memoranda for Civil and Mechanical Engineers. 
By Guilford L. Molesworth, Member of the Institution of Civil 
Engineers, Chief Resident Engineer of the Ceylon Railway. Full- 
bound in Pocket-book form ...... ^i.oo 



HENRY CAREY BAIRD & CO.'S CATALOGUE. 19 

MOORE. — The Universal Assistant and the Complete Me- 
chanic : 

Containing over one million Industrial Facts, Calculations, Receipts, 
Processes, Trades Secrets, Rules, Business Forms, Legal Items, Etc., 
in every occupation, from the Household to the Manufactory. By 
R. Moore. Illustrated by 500 Engravings. i2mo. . ^2.50 

MORRIS. — Easy Rules for the Measurement of Earthworks : 
By means of the Prismoidal Formula. Illustrated with Numerous 
Wood-Cuts, Problems, and Examoles, and concluded by an Exten- 
sive Table for finding the Solidity in cubic yards from Mean Areas. 
The vi^hole being adapted for convenient use by Engineers, Surveyors, 
Contractors, and others needing Correct Measurements of Earthwork. 
By Elwood Morris, C. E. 8vo $1.50 

MORTON. — The System of Calculating Diameter, Circumfer- 
ence, Area, and Squaring the Circle : 
Together with Interest and Miscellaneous Tables, and other informa- 
tion. By James Morton. Second Edition, enlarged, with the 
Metric System. i2mo. ....... ^i.oo 

NAPIER.— Manual of Electro-Metallurgy: 

Including the Application of the Art to Manufacturing Processes. 
By James Napier. Fourth American, from the Fourth London 
edition, revised and enlarged. Illustrated by engravings. 8vo. ^1.50 

NAPIER. — A System of Chemistry Applied to Dyeing. 

By James Napier, F. C. S. A New and Thoroughly Revised Edi- 
tion. Completely brought up to the present state of the Science, 
including the Chemistry of Coal Tar Colors, by A. A. Fesquet, 
Chemist and Engineer. With an Appendix on Dyeing and Calico 
Printing, as shown at the Universal Exposition, Paris, 1867. Illus- 
trated. 8vo. 422 pages ....... ^5.00 

NEVILLE.— Hydraulic Tables, Coefficients, and Formulae, for 
finding the Discharge of Water from Orifices, Notches, 
Weirs, Pipes, and Rivers : 
Third Edition, with Additions, consisting of New Formulae for the 
Discharge from Tidal and Flood Sluices and Siphons ; general infor- 
mation on Rainfall, Catchment-Basins, Drainage, Sewerage, Water 
Supply for Towns and Mill Power. By Iohn Neville, C. E. M. R. 
I. A. ; Fellow of the Royal Geological Society of Ireland. Thick 
I2mo. .......... ^^3.50 

NEWBERY. — Gleanings from Ornamental Art of every 
style : 
Drawn from Examples in the British, South Kensington, Indian, 
Crystal Palace, and other Museums, the Exhibitions of 185 1 and 
1862, and the best English and Foreign works. In a series of 100 
exquisitely drawn Plates, containing many hundred examples. By 
Robert Newbery. 4to. ^12.50 

NICHOLLS. —The Theoretical and Practical Boiler-Maker and 
Engineer's Reference Book: 
Containing a variety of Useful Information for Employers of Labor, 
Foremen and Working Boiler-Makers, Iron, Copper, and Tinsmiths, 



20 HENRY CAREY BAIRD & CO.'S CATALOGUE. 

Draughtsmen, Engineers, the General Steam-using Public, and for the 
Use of Science Schools and Classes. By Samuel Nicholls. Illus- 
trated by sixteen plates, lamo. ..... ^2.50 

NICHOLSON.— A Manual of the Art of Bookbinding : 

Containing full instructions in the different Branches of Forwarding, 
Gilding, and Finishing. Also, the Art of Marbling Book-edges and 
Paper. By James B. Nicholson. Illustrated. i2mo., cloth $2.25 

NICOLLS.— The Railway Builder: 

A Hand-Book for Estimating the Probable Cost of American Rail- 
way Construction and Equipment. By William J. Nicolls, Civil 
Engineer. Illustrated, full bound, pocket-book form . ^2.00 

NORMANDY.— The Commercial Handbook of Chemical An- 
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Or Practical Instructions for the Determination of the Intrinsic or 
Commercial Value of Substances used in Manufactures, in Trades, 
and in the Arts. By A. Normandy. New Edition, Enlarged, and 
to a great extent rewritten. By Henry M. Noad, Ph.D., F.R.S., 
thick l2mo ^5.00 

NORRIS. — A Handbook for Locomotive Engineers and Ma- 
chinists : 
Comprising the Proportions and Calculations for Constructing Loco- 
motives; Manner of Setting Valves; Tables of Squares, Cubes, Areas, 
etc., etc. By Septimus Norris, M. E. New edition. Illustrated, 
i2mo i?i.5o 

NORTH.— The Practical Assayer : 

Containing Easy Methods for the Assay of the Principal Metals and 
Alloys. Principally designed for explorers and those interested in 
Mines. By Oliver North. Illustrated. i2mo. . $2.<io 

NYSTROM. — A New Treatise on Elements of Mechanics : 
Establishing Strict Precision in the Meaning of Dynamical Terms : 
accompanied with an Appendix on Duodenal Arithmetic and Me- 
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NYSTROM. — On Technological Education and the Construc- 
tion of Ships and Screw Propellers : 
For Naval and Marine Engineers. By John W. Nystrom, late 
Acting Chief Engineer, U. S. N. Second edition, revised, with addi- 
tional matter. Illustrated by seven engravings. i2mo. . ^1.50 

O'NEILL. — A Dictionary of Dyeing and Calico Printing: 

Containing a brief account of all the Substances and Processes in 
use in the Art of Dyeing and Printing Textile Fabrics ; with Practical 
Receipts and Scientific Information. By Charles O'Neill, Analy- 
tical Chemist. To which is added an Essay on Coal Tar Colors and 
their application to Dyeing and Calico Printing. By A. A. Fesquet, 
Chemist and Engineer. With an appendix on Dyeing and Calico 
Pi-inting, as shown at the Universal Exposition, Paris, 1867. 8vo., 
491 pages ;g5.oo 

ORTON. — Underground Treasures*. 

How and Where to Find Them. A Key for the Ready Determination 
of all the Useful Minerals within the United States. By James 



HENRY CAREY BAIRD & CO.'S CATALOGUE. 



Orton, A.m., Late Professor of Natural History in Vassar College 
N. Y.; Cor. Mem. of the Academy of Natural Sciences, Philadelphia' 
and of the Lyceum of Natural History, New York ; author of the 
"Andes and the Amazon," etc. A New Edition, with Additions. 
Illustrated •••..,. fii eo 

OSBORN.— The Metallurgy of Iron and Steel : 

Theoretical and Practical in all its Branches ; with special reference 
to American Materials and Processes. By H. S. OsBORN, LL D 
Professor of Mining and Metallurgy in Lafayette College', Eas'ton' 
Pennsylvania. Illustrated by numerous large folding plates and 
wood-engravings. 8vo. ... #2t; oo 

OVERMAN.— The Manufacture of Steel : ' ' 

Containing the Practice and Principles of Working and Making Steel. 
A Handbook for Blacksmiths and Workers in Steel and Iron, Wagon 
Makers, Die Sinkers, Cutlers, and Manufacturers of Files and Hard- 
ware, of Steel and Iron, and for Men of Science and Art. By 
Frederick Overman, Mining Engineer, Author of the " Manu- 
facture of Iron," etc. A new, enlarged, and revised Edition. By 
A. A. Fesquet, Chemist and Engineer. lamo. . ^i ro 

OVERMAN.— The Moulder's and Founder's Pocket Guide : 
A Treatise on Moulding and Founding in Green-sand, Dry-sand, Loam, 
and Cement; the Moulding of Machine Frames, Mill-gear, Hollow- 
ware, Ornaments, Trinkets, Bells, and Statues ; Description of Moulds 
for Iron, Bronze, Brass, and other Metals ; Plaster of Paris, Sulphur, 
Wax, etc. ; the Construction of Melting Furnaces, the Melting and 
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etc., etc. By Frederick Overman, M. E. A new Edition, to 
which is added a Supplement on Statuary and Ornamental Moulding, 
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ist and Engineer. Illustrated by 44 engravings. i2mo. . ' ^2 00 
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PALLETT.— The Miller's, Millwright's, and Engineer's Guide. 
By Henry Pallett. Illustrated. i2mo. . . . ^3.00 
PEARSE.— A Concise History of the Iron Manufacture of the 
American Colonies up to the Revolution, and of Pennsyl- 
vania until the present time. 
By John B. Pearse. Illustrated i2mo. . . . ^2.00 



22 HENRY CAREY BAIRD & CO.'S CATALOGUE. 

PERCY. — The Manufacture of Russian Sheet-Iron. 

By John Percy, M. D., F. R. S., Lecturer on Metallurgy at the 
Royal School of Mines, and to The Advance Class of Artillery 
Officers at the Royal Artillery Institution, Woolwich; Author of 
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PERKINS.— Gas and Ventilation : 

Practical Treatise on Gas and Ventilation. With Special Relation 
to Illuminating, Heating, and Cooking by Gas. Including Scientific 
Helps to Engineer-students and others. With Illustrated Diagrams. 
By E. E. Perkins. i2mo., cloth ^1.25 

PERKINS AND STOWE.— A New Guide to the Sheet-iron 
and Boiler Plate Roller : 
Containing a Series of Tables showing the Weight of Slabs and Pilee 
to Produce Boiler Plates, and of the Weight of Piles and the Sizes of 
Bars to produce Sheet-iron ; the Thickness of the Bar Gauge 
in decimals ; the Weight per foot, and the Thickness on the Bar or 
Wire Gauge of the fractional parts of an inch ; the Weight per 
sheet, and the Thickness on the Wire Gauge of Sheet-iron of various 
dimensions to weigh 112 lbs. per bundle; and the conversion of 
Short Weight into Long Weight, and Long Weight into Short. 
Estimated and collected by G. H. Perkins and J. G. Stowe. $2.50 

POWELL— CHANCE— HARRIS.— The Principles of Glass 

Making. 

By Harry J. Powell, B. A. Together with Treatises on Crown and 

Sheet Glass; by Henry Chance, M. A. And Plate Glass, by H. 

G. Harris, Asso. M. Inst. C. E. Illustrated i8mo. . ^1.50 

PROTEAUX.— Practical Guide for the Manufacture of Paper 

and Boards. 

By A. Proteaux. From the French, by HoRATio Paine, A. B., 

M. D. To which is added the Manufacture of Paper from Wood, 

by Henry T. Brown. Illustrated by six plates. 8vo. . 1:12.50 

PROCTOR.— A Pocket-Book of Useful Tables and Formulae 
for Marine Engineers. 
By Frank Proctor. Second Edition, Revised and Enlarged. 
Full bound pocket-book form ...... ^1.50 

REGNAULT.— Elements of Chemistry. 

By M. V. Regnault. Translated from the French by T. Forrest 
Betton, M. D., and edited, with Notes, by James C. Booth, Melter 
and Refiner U. S. Mint, and William L. Faber, Metallurgist and 
Mining Engineer. Illustrated by nearly 700 wood engravings. Com- 
prising nearly 1,500 pages. In two volumes, Svo., cloth . J??. 50 

RIFFAULT, VERGNAUD, and TOUSSAINT.— A Practical 
Treatise on the Manufacture of Colors for Painting : 
Comprising the Origin, Definition, and Classification of Colors ; the 
Treatment of the Raw Materials ; the best Formulae and the Newest 
Processes for the Preparation of every description of Pigment, and 
the Necessary Apparatus and Directions for its Use; Dryers; the 
Testing, Application, and Qualities of Paints, etc., etc. By MM. 
Riffault, Vergnaud, and Toussaint. Revised and Edited by M. 



HENRY CAREY BAIRD & CO.'S CATALOGUE. 23 

F. Malepeyre. Translated from the French, by A. A. Fesquet, 
Chemist and Engmeer. Illustrated by Eighty engravings. In one 
vol., 8vo., 659 pages ^7-50 

ROPER. — A Catechism of High-Pressure, or Non- Condensing 
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Including the Modelling, Constructing, and Management of Steam- 
Engines and Steam Boilers. With valuable illustrations. By Ste- 
phen Roper, Engineer. Sixteenth edition, revised and enlarged. 
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ROPER.— Engineer's Handy-Book : 

Containing a full Explanation of the Steam-Engine Indicator, and its 
Use and Advantages to Engineers and Steam Users. With Formulae 
for Estimating the Power of all Classes of Steam-Engines ; also, 
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qualify themselves for the United Stales Navy, the Revenue Service, 
the Mercantile Marine, or to take charge of the Better Class of Sta- 
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gilt edge ^3.50 

ROPER. — Hand-Book of Land and Marine Engines : 

Including the Modelling, Construction, Running, and Management 
of Land and Marine Engines and Boilers. With il'ustrations. By 
Stephen Roper, Engineer. Sixth edition. i2mo.,t\'cks, gilt edge. 

$3-50 
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Including the Construction of Engines and Boilers, and the Construc- 
tion, Management, and Running of Locomotives. By STEPHEN 
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ROPER. — Hand-Book of Modern Steam Fire-Engines. 

With illustrations. By Stephen Roper, Engineer. Fourth edition, 
i2mo., tucks, gilt edge ....... ^^3.50 

ROPER. — Questions and Answers for Engineers. 

This little book contains all the Questions that Engineers will be 
asked when undergoing an Examination for the purpose of procuring 
Licenses, and they are so plain that any Engineer or Fireman of or- 
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Stephen Roper, Engineer. Third edition . . . ^3.00 

ROPER.— Use and Abuse of the Steam Boiler. 

By Stephen Roper, Engineer. Eighth edition, with illustrations. 
i8mo., tucks, gilt edge ....... ;^2.oo 

ROSE. — The Complete Practical Machinist : 

Embracing Lathe-Work, Vise-Work, Drills and Drilling, Taps and 
Dies, Hardening and Tempering, the Making and Use of Tools, Tool 
Grinding, Marking Out Work, etc. By JosHUA Rose, Author of " The 
Pattern-maker's Assistant " and " The Slide Valve." Illustrated by 
196 engravings. Eighth edition, revised and enlarged by the addition 
of much new matter. i2mo., 441 pages . . . ^2.50 

ROSE.— Mechanical Drawing Self-Taught: 

Comprising Instructions in the Selection and Preparation of Drawing 
Instruments, Elementary Instruction in Practical Mechanical Draw- 



24 HENRY CAREY BAIRD & CO.'S CATALOGUE. 

ing, together with Examples in Simple Geometry and Elementary 
Mechanism, including Screw Threads, Gear Wheels, Mechanical Mo- 
tions, Engines and Boilers. By Joshua Rose, M. E., Author of 
"The Complete Practical Machinist," " The Pattern-maker's Assist- 
ant," " The Slide-valve." Illustrated by 330 engravings. 8vo., 313 
pages ^4.00 

ROSE.— The Slide-Valve Practically Explained: 

Embracing simple and complete Practical Demonstrations of the 
operation of each element in b. Slide-valve Movement, and illustrating 
the effects of Variations in their Proportions by examples carefully 
selected from the most recent and successful practice. By JoSHUA 
Rose, M. E., Author of " The Complete Practical Machinist," " The 
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ROSS. — The Blowpipe in Chemistry, Mineralogy and Geology: 
Containing all Known Methods of Anhydrous Analysis, many Work- 
ing Examples, and Instructions for Making Apparatus. By LlEUT.- 
COLONEL W. A. Ross, R. A. F., G. S. With I2q Illustrations. 
i2mo ^1.50 

SHAW.— Civil Architecture : 

Being a Complete Theoretical and Practical System of Building, con- 
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By Thomas W. Silloway and George M. Harding, Architects. 
The whole illustrated by 102 quarto plates finely engraved on copper. 
Eleventh edition. 4to. ....... $10.00 

SHUNK. — A Practical Treatise on Railway Curves and Loca- 
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By William F. Shunk, Civil Engineer. i2mo. Full bound pocket- 
book form ......... $2.00 

SLATER.— The Manual of Colors and Dye Wares. 

By J. W. Slater. i2mo $3-75 

SLOAN. — American Houses : 

A variety of Original Designs for Rural Buildings. Illustrated by 
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Samuel Sloan, Architect, author of the " Model Architect," etc. 
etc. 8vo ^1.50 

SLOAN. — Homestead Architecture : 

Containing Forty Designs for Villas, Cottages, and Farm-houses, with 
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SM EATON. —Builder's Pocket-Companion : 

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SMITH. — A Manual of Political Economy. 

By E. Peshine Smith. A new Edition, to which is added a full 
Index. i2mo. •^1.25 



HENRY CAREY BAIRD & CO.'S CATALOGUE. 25 

SMITH. — Parks and Pleasure-Grounds : 

Or Practical Notes on Country Residences, Villas, Public Parks, and 
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SMITH.— The Dyer's Instructor: 

Comprising Practical Instructions in the Art of Dyeing Silk, Cotton, 
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SMYTH.— A Rudimentary Treatise on Coal and Coal-Mining. 
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SNIVELY. — A Treatise on the Manufacture of Perfumes and 
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SNIVELY.— Tables for Systematic Qualitative Chemical Anal- 
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SNIVELY.— The Elements of Systematic Qualitative Chemical 
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^2.00 

STEWART.— The American System : 

Speeches on the Tariff Question, and on Internal Improvements, 
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STOKES. — The Cabinet-Maker and Upholsterer's Companion : 
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STRENGTH AND OTHER PROPERTIES OF METALS: 
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SULLIVAN. — Protection to Native Industry. 

By Sir Edward Sullivan, Baronet, author of " Ten Chapters on 
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26 HENRY CAREY BAIRD & CO.'S CATALOGUE. 

SYME. — Outlines of an Industrial Science. 

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TABLES SHOWING THE WEIGHT OF ROUND, 
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By Measurement. Cloth ...... 63 

TAYLOR.— Statistics of Coal : 

Including Mineral Bituminous Substances employed in Arts and 
Manufactures; with their Geographical, Geological, and Commercial 
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TEMPLETON. — The Practical Examinator on Steam and the 
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THAUSING.— The Theory and Practice of the Preparation of 
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With especial reference to the Vienna Process of Brewing. Elab- 
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THOMAS. — The Modern Practice of Photography: 

By R. W. Thomas, F. C. S. 8vo. .... 75 

THOMPSON.— Political Economy. With Especial Reference 
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THOMSON.— Freight Charges Calculator: 

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TURNER'S (THE) COMPANION: 

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URBIN— BRULL.— A Practical Guide for Puddling Iron and 
Steel. 
By E.D. Urbin, Engineer of Arts and Manufactures. A Prize Essay, 



HENRY CAREY BAIRD & CO.'S CATALOGUE. 27 

read before the Association of Engineers, Graduate of the School of 
Mines, of Liege, Belgium, at the Meeting of 1865-6. To which is 
added A Comparison of the Resisting Properties of Iron and 
Steel. By A. Brull. Translated from the French by A. A. Fes- 
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VAILE.— Galvanized-Iron Cornice-Worker's Manual: 

Containing Instructions in Laying out the Different Mitres, and 
Making Patterns for all kinds of Plain and Circular Work. Also, 
Tables of Weights, Areas and Circumferences of Circles, and olher 
Matter calculated to Benefit the Trade. By Charles A. Vaile. 
Illustrated by twenty-one plates. 4to ^S-OO 

VILLE. — On Artificial Manures : 

Their Chemical Selection and Scientific Application to Agriculture. 
A series of Lectures given at the Experimental Farm at Vincennes. 
during 1867 and 1874-75. By M. Georges Ville. Translated and 
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VILLE.— The School of Chemir,al Manures : 

Or, Elementary Principles in the Use of Fertilizing Agents. From 
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VOGDES. — The Architect's and Builder's Pocket-Companion 
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form, gilt edges . ^2.00 

Cloth . . 1.50 

WAHL.— Galvanoplastic Manipulations : 

A Practical Guide lor the Gold and Silver Electroplater and the Gal- 
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as well as the most approved Processes of Deposition by Simple Im- 
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WALTON. — Coal-Mining Described and Illustrated : 

By Thomas H. Walton, Mining Engineer. Illustrated by 24 large 
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{^In press. ^ 



\ 



28 HENRY CAREY BAIRD & CO.'S CATALOGUE. 

WARE.— The Sugar Beet. 

Including a History of the Beet Sugar Industry in Europe, Varieties 
of the Sugar Beet, Examination, Soils, Tillage, Seeds and Sowing, 
Yield and Cost of Cultivation, Harvesting, Transportation, Conserva- 
tion, Feeding Qualities of the Beet and of the Pulp, etc. By Lewis 
S. Ware, C. E., M. E. Illustrated by ninety engravings. 8vo. 

$4.00 
WARN. — The Sheet-Metal Worker's Instructor: 

For Zinc, Sheet-Iron, Copper, and Tin-Plate Workers, etc. Contain- 
ing a selection of Geometrical Problems ; also, Practical and Simple 
Rules for Describing the various Patterns required in the different 
branches of the above Trades. By Reuben H. Warn, Practical 
Tin-Plate Worker. To which is added an Appendix, containing 
Instructions for Boiler- Making, Mensuration of Surfaces and Solids, 
Rules for Calculating the Weights of different Figures of Iron and 
Steel, Tables of the Weights of Iron, Steel, etc. Illustrated by thirty- 
two Plates and thirty-seven Wood Engravings. Svo. . ^3.00 

WARNER. — New Theorems, Tables, and Diagrams, for the 
Computation of Earth-work : 

Designed for the use of Engineers in Preliminary and Final Estimates, 
of Students in Engineering, and of Contractors and other non-profes- 
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Treatise upon Equivalent Square Bases and Equivalent Level Heights. 
The whole illustrated by numerous original engravings, comprising 
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and Diagrams, and a series of Lithographic Drawings from Models : 
Showing all the Combinations of Solid Forms which occur in Railroad 
Excavations and Embankments. By JOHN WARNER, A. M., Mining 
and Mechanical Engineer. Illustrated by 14 Plates. A new, revised 
and improved edition. Svo. ...... M-OO 

WATSON.— A Manual of the Hand-Lathe : 

Comprising Concise Directions for Working Metals of all kinds, 
Ivory, Bone and Precious Woods ; Dyeing, Coloring, and French 
Polishing; Inlaying by Veneers, and various methods practised to 
produce Elaborate work with Dispatch, and at Small Expense. By 
Egbert P. Watson, Author of " The Modern Practice of American 
Machinists and Engineers." Illustrated by 78 engravings. $i.SO 

WATSON. — The Modern Practice of American Machinists and 
Engineers : 

Including the Construction, Application, and Use of Drills, Lathe 
Tools, Cutters for Boring Cylinders, and Hollow-work generally, with 
the most Economical Speed for the same ; the Results verified by 
Actual Practice at the Lathe, the Vise, and on the Floor. Together 



HENRY CAREY BAIRD & CO.'S CATALOGUE. 29 



with Workshop Management, Economy of Manufacture, the Steam- 
Engine, Boilers, Gears, Belting, etc., etc. By Egbert P. Watson. 
Illustrated by eighty-six engravings. i2mo. . . . ^2.50 

WATSON.— The Theory and Practice of the Art of Weaving 
by Hand and Power : 
With Calculations and Tables for the Use of those connected with the 
Trade. By John Watson, Manufacturer and Practical Machine- 
Maker. Illustrated by large Drawings of the best Power Looms. 
^^°- . . . • ;^7.5o 

WATT.— The Art of Soap Making : 

A Practical Hand-book of the Manufacture of Hard and Soft Soaps, 
Toilet Soaps, etc., including many New Processes, and a Cliapter on 
the Recovery of Glycerine from Waste Leys. By Alexander 
Watt. 111. i2mo. fe.oo 

WEATHERLY.— Treatise on the Art of Boiling Sugar, Crys- 
tallizing, Lozenge-making, Comfits, Gum Goods, 

And other processes for Confectionery, etc., in which are explained, 
in an easy and familiar manner, the various Methods of Manufactur- 
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Confectioners and others. i2mo. ..... $1.50 

WEDDING.— Elements of the Metallurgy of Iron. 

By Dr. Hermann Wedding, Royal Privy Counsellor of Mines, Ber- 
lin, Prussia. Translated froih the second revised and rewritten Ger- 
man edition. By William T. Brannt, Graduate of the Royal Ag- 
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Wahl, Ph. D., Secretary of the Franklin Institute, Philadelphia. 
Illustrated by about 250 engravings. 8vo., about 500 pages {In prep- 
aratio7t.^ . . . ... 

WEINHOLD. — Introduction to Experimental Physics, Theo- 
retical and Practical. 
Including directions for Constructing Physical Apparatus and for 
Making Experiments. By Adolf F. Weinhold, Professor in the 
Royal Technical School at Chemnitz. Translated and edited, with 
the author's sanction, by Benjamin Loewy, F. R. A. S., with a 
preface, by G. C. Foster, F. R. S. Illustrated by three colored plates 
and 404 wood-cuts. 8vo., 848 pages .... ^6.00 

WIGHTWICK.— Hmts to Young Architects: 
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WILL. — Tables of Qualitative Chemical Analysis. 

With an Introductory Chapter on the Course of Analysis. By Pro- 
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30 HENRY CAREY BAIRD & CO.'S CATALOGUE. 

from the eleventh German edition. Edited by Charles F. Himes, 

Ph. D., Professor of Natural Science, Dickinson College, Carlisle, Pa. . "4^ 

8vo. . . • ^1.50 

WILLIAMS.— On Heat and Steam : 

Embracing New Views of Vaporization, Condensation, and Explo- 
sion. By Charles Wye Williams, A. I. C. E. Illustrated 8vo. 

$3 SO 
WILSON. — A Treatise on Steam Boilers : 

Their Strength, Construction, and Economical Working. By Robert 
Wilson. Illustrated i2mo ^2.50 

WILSON. — Cotton Carder's Companion: 

In which is given a description of the manner of Picking, Baling, 
Marketing, Opening, and Carding Cotton; to which is added a list of 
valuable Tables, Rules, and Receipts, by Foster Wilson. i2mo. 

^1.50 

WILSON. — First Principles of Political Economy : 

With Reference to Statesmanship and the Progress of Civilization. 
By Professor W. D. WiLSON, of the Cornell University. A new and 
revised edition. l2mo. ....... ^1.50 

WOHLER.— A Hand-book of Mineral Analysis. 

By F. WoHLER, Professor of Chemistry in the University of Gottin- 
gen. Edited by Henry B. Nason, Professor of Chemistry in the 
Renssalaer Polytechnic Institute, Troy, New York. Illustrated 
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WORSSAM.— On Mechanical Saws : 

From the Transactions of the Society of Engineers, 1869. By S. W'. 
WoRSSAM, Jr. Illustrated by eighteen large plates. 8vo. . #2.50 



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